TW201908201A - Airplane wing - Google Patents

Abstract

The invention relates to a wing with two winglets and a respective airplane. An upstream winglet broadens a region of inclined airflow and a downstream winglet produces a thrust contribution therein.

Description

 Aircraft wing  

The present invention relates to an aircraft and a wing for an aircraft.

Aircraft are one of the most important means of transportation for people and goods, as well as for military applications, and for most long-distance travel, there is almost no substitute for the aircraft. The present invention relates to aircraft in the sense of not including a helicopter, and the present invention relates to a wing for an aircraft in the sense of not including a rotor blade of a helicopter. In particular, the present invention relates to aircraft having a fixed wing and such fixed wings themselves.

The basic function of a motorized aircraft and its wings is to generate a certain speed by propelling the engine and to generate the required lift in the airflow caused by the speed by the wing of the aircraft. This function is the subject of the aerodynamic design of the wing of the aircraft, for example, regarding their size, profile, and the like.

It is generally known to use so-called wingtip devices or winglets at the outer ends of the main wing of the aircraft (i.e., those that are primarily or exclusively responsible for lift). These winglets should reduce the so-called wingtip vortex created by the pressure difference between the upper and lower regions of the wing, which is the cause of the expected lift. Because the wing has an end, the airflow tends to compensate for the pressure differential that would cause the vortex. This tip vortex reduces the lifting effect of the wing, increases the noise generated, increases the energy loss due to dissipation in the airflow, and may be detrimental to other aircraft that are following the aircraft. The winglet can be said to be a baffle of a wing tip vortex.

The subject of the present invention is to provide an improved wing with a winglet and an improved individual aircraft.

In order to solve this problem, the present invention relates to a wing for an aircraft, the wing comprising: an outer wing end for mounting to the inside of the aircraft relative to the wing, on the opposite side of the wing At least two winglets are attached to the wing at the outer wing end, and the first winglet upstream of the winglets is tied downstream of the winglets in the flight direction of the wing In front of the winglet, as seen against its flight direction, the first winglet and the second winglet are inclined with respect to each other by a relative double-sided angle δ1, δ2 in a range of 5° to 35°, wherein The first winglet is inclined upward relative to the second winglet, wherein the opposite double-sided angle is defined as the root of the winglet having an isosceles triangle having a vertex at its root, that is, at a level In the direction of the splitting point of the two winglets in the direction, and in the middle of the position of the leading edge of the winglets in the vertical direction, the opening angle, one vertex is on the leading edge of the first winglet, and one vertex is in the second On the front edge of the winglet, as seen in the projection against its flight direction, the triangle has Having a variable length of two equal triangular sides, and the double-sided angular interval is effective for at least 70% of the equilateral length along the shorter of the first winglet and the second winglet; And, with respect to an aircraft having two such wings facing each other, and for use with an upgraded component, the upgraded components include individual winglets for mounting to an aircraft to produce such Wing or airplane.

The invention relates to a wing having at least two winglets, wherein the winglets are fixed to the outer wing ends of the wing. To avoid misunderstanding, the "wing" may be the main wing of the aircraft (primarily) responsible for the required lift; however, it may also be a horizontal stabilizer that is generally also substantially horizontal. Furthermore, the term "wing" should be a wing that extends from the base of the aircraft and extends outward therefrom. At the outer wing end of the wing, at least two winglets are fixed and further (but not necessarily) extend in the same direction. As is known in the art, a winglet can be tilted and/or bent relative to the wing. Preferably, however, the winglets do not extend inwardly from the outer wing end.

The inventors have found that the mutual inclination of the two winglets viewed against the flight direction leads to advantageous results in quantitative evaluation by computer fluid dynamics calculations. In particular, it has proven to be advantageous to tilt the upstream first winglet relative to the second winglet, for example, preferably the upstream first winglet is inclined more upward than the second winglet. Among them, the difference in inclination, the so-called difference in double-sided angle (relative double-sided angle), should be moderate, that is, no more than 35°. On the other hand, a certain relative double-sided angle should be viewed and should not be less than 5°. More preferably, the lower limit of the opposite double-sided angle interval (in the following order) is 7°, 9°, 11°, 13°, and 15°, and more preferably, the upper limit of the opposite double-sided angle interval is 33°, 31°, 29°, 27° and 25°. Therefore, the optimal value should be approximately 20°.

The results of the present invention show that this relative double-sided angle is more important than the absolute double-sided angle of the two winglets, possibly because the airflow geometry is at the end of the main wing and thus at the root of the winglets, It has a certain rotational symmetry about an axis parallel to the flight direction. This is of course only an approximate statement, but nevertheless, the relative double-sided angle is considered to be more important than the absolute double-sided angle.

The relative double-sided angles here are averaged, that is, by the isosceles triangle between the vertices. A vertex should be at its root and a separate vertex on each winglet. More precisely, its triangle is defined by a projection against the direction of flight, and, as far as its horizontal dimension, the apex at its root should be at the splitting point of the two winglets, ie at the level of vertical viewing. Dimensions, the two winglets are separated from that place. As for the vertical dimension, the root apex should be in the middle of the position of the leading edge (the most upstream edge) of the two winglets in the horizontal position just described, or if they overlap there, at that position. Since this region is a smooth transition shape to avoid aerodynamic disturbances, it can be said that its front edge loses its position in this transition region (the so-called fairing between the winglets and the main wing ends). Identification. Therefore, the leading edges should be inferred by ignoring the inner portion of the 10% of the spanwise length of the winglet (as defined in more detail below) and, for other reasons, ignoring between 90% and 100% The outer portion (ie, the possible fillet as described in the specific example). The remaining 10%-90% represent the appropriate leading edge that can be inferred. If the leading edge is not straight, you can use the average line to infer.

The vertices on the winglets should be on their leading edges, respectively. Therefore, the opening angle of the triangle, that is, the angle between the two equal sides, is the opposite double-sided angle.

The triangle definition includes a variable length of the equilateral edge within the limits imposed by the shorter of the two winglets. With respect to this variable side length concept, the defined relative double-sided angular interval is effective for at least 70% of the side length, more preferably at least 75%, 80%, 85%, or even 90% of the side length. In other words, if a small portion of the winglets does not belong to the opposite double-sided corner interval, this is not detrimental to the present invention, however, 100% is of course the best in this interval.

The variable side length concept takes into account that the winglets need not be straight (in a view angle against the direction of flight), but may for example follow a circular portion shown in the specific example for the first winglet Bend completely or partially. The winglets may also be polygonal (having a finite angle) or shaped such that their opposite dihedral angles vary along their spanwise length. Furthermore, even with straight winglets (viewed against the direction of flight), their leading edge lines do not necessarily coincide with the root vertices defined above, which may cause the relative double-sided angles to vary slightly along their length. . However, with straight winglets, the opposite double-sided angle defined by the concept of triangles is at least approximately the angle that is visible against the direction of flight.

The geometry of the wing and the many winglets above and all of the following descriptions are related to the "in flight" shape that the expert knows. In other words, these descriptions and definitions relate to flight conditions, where aerodynamic performance should be and is relevant, which is basically a typical flight speed (depending on distance) at typical flight altitudes. Experts are familiar with another "jig shape", which should be based on the shape of the wing and many winglets in a non-flight state, that is, without any aerodynamic forces on them. Any difference between the shape of the frame and the shape in flight is caused by the elastic deformation of the wing and the winglets on which aerodynamic forces act. The precise nature of these elastic deformations depends on the static mechanical properties of the wing and winglet configurations that may vary from case to case. This is also a familiar concept for mechanical engineers, and such deformations can be calculated and predicted in a finite element calculation, for example, simply using a standard computer simulation program.

The reference to the shape of the profile in this specification will therefore not make much sense since aerodynamic performance is a relevant category. Furthermore, the mechanical structure of the wings and winglets of the present invention may vary from case to case, so that any assumption as to how the shape of the profile is transformed into an in flight shape would be impractical.

In addition, the terms "horizontal" and "vertical" relate to the state in which the wing is mounted on the aircraft, where "vertical" is the direction of gravity and "horizontal" is perpendicular to it.

The relative inclination of the winglets described above has proven to be advantageous in terms of trade-off between the two aspects. On the one hand, a zero or very small number of opposite double-sided angles results in: the downstream winglet (here, the second winglet) is subject to the airflow affected by the upstream (here, first) winglet and is subject to tight The turbulence or even the diffusion of the upstream winglets is suppressed, thus suppressing proper and significant aerodynamic performance, for example, the generation of lift and/or thrust contributions described below. In contrast, the downstream winglets may produce more resistance than expected, which is lift, thrust, vortex disappearance, and so on.

On the other hand, it can be said that the too large relative double-sided angle "decouples" the winglets to each other, however, the present invention intends to use the synergistic effect of at least two winglets. In particular, the present invention preferably It is intended to regulate the airflow with the upstream winglets for the downstream winglets. In particular, one aspect of the invention will use the inclined airflow in the region of the tip vortex of the wing in a positive sense. Another idea would be to have a positive thrust. The aerodynamic "lift" is generated in the slanted airflow of the component (i.e., the forward component parallel to the flight direction of the aircraft). It should be clear here that "lift" is related to the aerodynamic wing function of the winglet. However, It is not necessarily important to maximize or even generate lift in an upward direction, but the forward thrust component is of interest.

In this regard, the inventors have discovered that "expanding" the inclined airflow is advantageous in order to improve its use. This makes sense because the wing tip vortex is so concentrated that it can be found that only the angle of inclination of the airflow direction (relative to the direction of flight) is quite close to the wing tip. Thus, in accordance with a preferred aspect, the present invention provides at least two winglets, one upstream winglet for "expanding" the region of the slanted airflow, and a downstream winglet for generating a thrust component therefrom.

The upstream winglet is thus used to split the wing tip vortex by "shifting" a portion of the wing tip vortex to the winglet tip (i.e., outward). As a result, the tip vortex (winglet tip vortex) caused by the winglet is superimposed with the vortex of the "remaining portion" of the wing (the wing is deeper in the flight direction than the winglet).

In this sense, the above-mentioned relative double-sided angular interval is advantageous.

Preferably, the winglets represented by the respective chord lines (lines between the leading edge of the wing and the most downstream point) should also rotate about a horizontal axis that is perpendicular (not parallel) to the flight mode. Ways to tilt. The angle of rotation is named the angle of inclination and should be positive in the case of a clockwise rotation of the winglet (viewed from the left side of the aircraft and vice versa from the right side of the aircraft). In this sense, the angle range of the first winglet from -15° to -5° is preferred, and more preferably combined with the angle range of the second winglet from -10° to 0°. These intervals are related to the roots of the winglets, and their pitch intervals are defined by a variable meaning that is linear with respect to the position along the spanwise length of the winglets. It should be displaced by +2° from the root to the tip of each winglet, which causes the first winglet and the second winglet to have a range from -13° to -3° at their respective tips. And from -8 ° to +2 ° interval. This does not necessarily mean that the actual dip of an implementation must be distorted, and the distortion represents a variable dip in the sense. A practical implementation can also be within the defined range without any distortion. However, since the inventors have considered that the airflow variation depends on the distance from the roots of the winglets, the appropriate dependence of the interval definition in this sense is appropriate (in other words, the center of the interval and its boundary). Being "distorted").

As described above, the inclination angle is defined between the chord of each winglet and the chord of the wing (host wing). The latter chord is in a position close to the wing splitting into a plurality of winglets (in other words, where the winglets are separated further outward) (in the direction of the water perpendicular to the direction of flight). Because, at its split position, the main wing may have been somewhat deformed (in terms of the fairing) in order to provide a smooth transition to the winglets, so the chord is tied a little more inward, ie At the further inward 10% of the length of the main wing. Conversely, it is equally applicable to the winglets such that the chord is further 10% outward at its split position.

A more preferred lower limit of the inclination range of the first winglet is -14°, -13°, -12° and -11° at the root thereof, and +2° is added to the value at the tip end thereof, and more preferably The upper limit is -6°, -7°, -8° and -9° at the root of the first winglet and, in addition, +2° at the tip end. Similarly, a more preferred lower limit of the second winglet is -9°, -8°, -7°, -6° at its root, and a more preferred upper limit is -1°, -2°, -3 °, -4°, in addition, add +2° to the tip.

Furthermore, the defined angular interval should be effective for at least 70% (more preferably, at least 75%, 80%, 85% and even 90%) of the length of the individual winglets. In other words, a small part of the winglets that do not meet these criteria is non-essential.

With regard to the inclination of the first winglet, it is advantageous to use the defined interval in order to minimize its resistance and not generate too much underflow downstream downstream of the first winglet. Too many underwashes can impede the function of the second winglet based on the inclination of the airflow due to the described vortex. The interval given for the second winglet has proven to be advantageous in terms of optimal thrust contribution. In many cases, it can also be seen from the given interval that the actual inclination of the first winglet will be less than the actual angle of inclination of the second winglet because the airflow downstream of the first winglet has been altered. The defined interval in any case and, in most cases, the small angle of inclination of the first winglet compared to the second winglet is the general result of the x-state simulation of the computer fluid implemented.

Preferably, the present invention also includes a third winglet downstream of the second winglet, and more preferably, the invention is limited to the three winglets (each wing).

More preferably, the third winglet conforms to a more preferred lower and upper limit (i.e., from 5° to 35°) of the opposite double-sided angle between the first winglet and the second winglet. The relative double-sided angle of the second winglet (but independently revealed). This double-sided angular difference value is understood to be that the second winglet is tilted (preferably, more upward) relative to the third winglet. The definition of the opposite double-sided angle is similar to that described above, but is of course related to the second and third winglets.

As described in relation to the relationship between the first winglet and the second winglet and their relative double-sided angles, also in the retrospective relationship between the second winglet and the third winglet, the third winglet is placed directly The "back" of the second winglet upstream is unfavorable, and decoupling them in the aerodynamic sense is also disadvantageous. Instead, by the relatively double-sided angle within a given interval, the third winglet will again be in a synergistic effect downstream of the first winglet and the second winglet (specifically, as preferred by the present invention, again The position at which the thrust contribution is generated.

More preferably, as described above for the first winglet and the second winglet (including the description of the definition of the chord line), the third winglet is also subject to the restriction of the angle of inclination in a similar manner. Here, for the third winglet, the interval should be from -7° to +3° at the root and, in addition, +2° at the tip, and should be a linear interpolation therebetween. A more preferred lower limit of the inclination range of the third winglet at the root is -6°, -5°, -4°, -3°, and a more preferable upper limit is +2°, +1°, 0°, - 1° and +2° at the tip. Moreover, the relative double-sided angle and the range of the dip angle are preferably at least 70% of the shorter of the second winglet and the third winglet, and are effective for the spanwise length of the third winglet. Further, a more preferred limit is at least 75%, 80%, 85%, 90%.

The above selection function of the inclination angle of the third winglet is similar to the selection function of the inclination angle of the second winglet, that is, the airflow encountered by the third winglet has been changed by the two upstream winglets, and the third winglet is intended This produces a thrust contribution while at the same time minimizing the drag of the entire system.

In another preferred embodiment, the so-called sweep angle of the two or three winglets is within a range of -5 to 35 degrees with respect to the swept angle of the main wing (positive values indicate "backward"). In other words, the winglets can be tilted back like an airplane wing in an arrow-like manner, preferably as much as the main wing or even more inclined. Among them, the sweep angles of all three winglets do not have to be the same. A more preferable lower limit is -4, -3, -2, -1, and a more preferable upper limit is 30, 25, 20, and 15 . As just described, the sweep angle is related to the inclination of the leading edge of each winglet relative to a horizontal line that is perpendicular to the direction of flight. This can be defined in the fictitious horizontal position of the winglet (the double-sided angle and the angle of inclination are zero and in any unfolded state of the bend). Alternatively, the sweep angle may be defined by replacing the actual extension of the winglet in a horizontal direction perpendicular to the direction of flight (as seen vertically) by the spanwise length b defined elsewhere in this application.

If the leading edge is not linear, the sweep angle is related to the average of the nonlinear leading edges in the range of 20% to 80% of the respective wingspans of the winglets. This limited span range is considered to be such that its leading edge may be deformed by a rounded corner at the outer end (for example in a specific example) and by a transition on the so-called rectifying portion at the inner end. Since the sweep angle is very sensitive to such effects, 20% replaces 10% as a "cut-off" at the boundary.

As for the reference, the range of the leading edge of the main wing, its wingspan of 50% to 90%, and the average line within this range should be considered. This is because the 0% spanwise position is usually in the middle of its base and is therefore not in the main wing itself, and there is a so-called belly rectification on the transition from the base to the main wing. It is constructed to form a proper wing shape and is a transition to the wing shape. Further, in any case, the winglet swept angles are adapted to the outside of the main wing.

The completed simulation has shown that the results can be optimized by some of the increased sweep angles of the winglets, but this angle should not be exaggerated. Since the sweep angle is related to the general speed range of the aircraft, a pragmatic and technically meaningful reference is made from the swept angle of the main wing.

Regarding their "polarity", in other words, regarding a downward tilt of a downstream winglet relative to an upstream winglet, the above description of the relative double-sided angle has been deliberately disclosed. In fact, the inventors have discovered that aerodynamic performance is relatively insensitive in this regard. Preferably, however, the upstream first winglet is more inclined upwards (with or without the third winglet) than the second winglet. Further and independently, it is preferred that the third winglet, if any, is inclined further downward than the second winglet. The best results achieved so far are based on the concepts shown in the specific examples.

Although it has been explained above, the relative double-sided angle between the first winglet and the second winglet (also between the second winglet and the third winglet) is different from the respective double-sided angles of the winglets The absolute value is also important, but the latter is also a better choice. For the first winglet, the respective double-sided corners range from -45° to -15°, and the lower limits are -43°, -41°, -39°, -37° and -35°, and more The upper limits are preferably -17°, -19°, -21°, -23° and -25°.

For the second winglet, all of these values are shifted by +20°, including these better limits. The same applies to the third winglet associated with the second winglet, if any. Moreover, these angular intervals are effective for at least 70%, preferably at least 75%, 80%, 85% or even 90% of the respective spanwise lengths of the winglets.

For the sake of clarity: the above mentioned relative double-sided angle limits are applicable in this case. If, for example, the double-sided angle of the first winglet is selected to be -35°, the interval of the double-sided angle of the second winglet is automatically limited to no more than 0°. These relative double-sided corner definitions are thus dominant. Furthermore, the absolute double-sided angle is defined in a manner similar to the relative double-sided angle, except that one of the equilateral sides of the isosceles triangle is horizontal rather than in the winglets. On the leading edge of one.

It has been found that the absolute value of the double-sided angle too low (for example, below -45°) and thus the upward orientation of the winglets may be disadvantageous because it is more difficult to be at the outer end of the main wing and the winglet. Provide an appropriate and smooth transition (rectifier). In addition, numerical simulations do not show any advantage of such a very low double-sided angle. On the other hand, very large values, i.e., the winglets are directed downwards, for example, with a double-sided angle of greater than 25°, which may have an adverse effect of reducing the height from the ground. Of course, the effect described for very low values also exists for very large values, but the difference between the boundaries of -45° and +25° shows that the height above the ground is usually the dominant surface. (However, there are exceptions, for example, so-called high-wing aircraft are less sensitive to ground height). Therefore, a double-sided angle from one of these limits to the other is generally preferred, and in the interval defined above for the first winglet, the second winglet, and the third winglet Even better.

As for the respective lengths of the winglets and the direction of the direction of the wings, a certain proportion of the length of the wings of the wing (main wing) is preferred, that is, from 2% to 10% for the first winglet, The second winglet is from 4% to 14%, and, if any, from 3% to 11% for the third winglet. The preferred lower limits for the respective first winglets are 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%. The preferred upper limits for the first winglets are 9.5%, 9.0%, 8.5%, 8.0%, 7.5%, 7.0%. For the second winglet, the lower limit is 5.0%, 6.0%, 6.5%, 7.0%, 7.5%, 8.0%, and the upper limit is preferably 13%, 12%, 11.5%, 11.0%, 10.5%. , 10.0%. Finally, the lower limit of the third winglet is 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, 6.0%, and, more preferably, the upper limit is 10.5%, 10.0%, 9.5%, 9.0%, 8.5. % and 8.0%.

The spanwise length is here defined as from the root of the winglets (ie, where the winglets are separated from the adjacent winglets, and where the second winglet is between the first winglet and the third winglet) , the innermost separation thereof) to the distance they are in the direction perpendicular to the flight direction and under the assumption that the inclination angle and the double-sided angle are zero (that is, the winglet is in the horizontal position). In the case of a non-linear shape of the winglet (for example, as in the curved portion of the first winglet in the specific example), the spanwise length is related to a fictitious straight line shape ("expanded" state) because, such The bending system is an alternative to double-sided tilting. More specifically, it is about a plane of projection perpendicular to the direction of flight, and in that it is about the length of the wing in terms of the middle line between the upper and lower limits of the projected winglet. For the main wing, the same definition is maintained, but starting from the middle of its base (half of the wingspan). The length of the main wing is measured until it is divided into a number of winglets; it is not the length of the entire wing including the winglets.

As regards the aforementioned relative length intervals of the winglets, these dimensions have proven to be practical and effective in terms of the typical dimensions of the tip vortex of the main wing of the nature of the winglets. Too small (too short) winglets are not able to take advantage of all the opportunities, and too small winglets with their respective winglet tips enter the area where the tip vortex of the main wing is too weak, so that the tilt cannot be utilized The entire length of the airfoil (especially the second and third winglets), and the above-described expansion effect as a particularly preferred concept of the present invention, would be more likely to produce two separate vortex fields instead of two Superimposed vortex fields.

Furthermore, there is a preferred relationship between the span lengths of the winglets, i.e., the second winglet preferably has a length of 105% to 180% of the first winglet. Likewise, preferably, the length of the third winglet is between 60% and 120% of the length of the second winglet. Among them, the lower limit of the first interval is 110%, 115%, 120%, 125%, 130%, 135% and 140%, and the upper limit is 175%, 170%, 165% and 160%. A preferred lower limit for the second zone is 65%, 70%, and 75%, and a more preferred upper limit is 115%, 110%, 105%, 100%, 95%, and 90%.

In a more general sense, it is preferred that the second winglet is at least as long (expanded) as the third winglet, preferably longer than the third winglet, and the third winglet (and thus The second winglet is also at least as long as the first winglet, preferably longer than the first winglet. This is basically due to the fact that the second winglet should make full use of the enlarged inclined airflow area expanded by the first winglet in order to produce maximum effect, and that the third winglet should again produce a similar or similar effect, but will This cannot be done because the energy has been removed from the airflow. Therefore, the size should be limited so as not to cause too much resistance.

Further, the chords of the winglets are preferably in the interval of 3 to 7, wherein the lower limit is 3.5 and 4.5, and the upper limit is 6.5, 6.0 and 5.5. As any quantitative limitation herein, this is specifically related to each winglet, and there are specific examples of the two winglets, in which there is more space in the chord direction. For a specific example of the three winglets, the aspect ratio may be somewhat high, and is preferably in the range of 4 to 9, with a preferred lower limit of 4.5 and 5.0, and a better upper limit of 8.5, 8.0 and 7.5. This again relates to each winglet individually.

Although higher aspect ratios are more efficient in the aerodynamic sense, they have a smaller area and thus produce less force (and thus a small thrust). In other words, a comparable winglet area is preferred over the length limits already described. On the other hand, a too low aspect ratio will increase the resistance, and in the end will reduce the effective thrust with increased resistance and reduce efficiency. In summary, the CFD simulation repeatedly shows an optimum value of about 5.

The aspect ratio is defined as dividing the chord length (i.e., the average) by twice the span length of the wing (i.e., in the case of the main wing, the entire span of the aircraft), again, except The wingspan is twice the length of the exhibition. Accurately, when estimating the chord length, the definition of 10% outside the span length in the present application is also effective here to exclude the rectification result and/or the fillet of the winglet. influences.

The preferred embodiment of the winglet of the present invention can have a certain root chord length. The values are defined for both cases (i.e., exactly the case of two winglets and exactly three winglets). For the two winglets, the root chord length of the first winglet may be in the range of 25% to 45% of the chord length (not at the root of the main wing) that the main wing splits into near the winglets.

In this case, for the second winglet, the respective preferred intervals are 40% to 60%. The lower limit of the first winglet is 27%, 29%, 31%, and the lower limit of the second winglet is 42%, 44%, 46%; the upper limit of the first winglet is better. 43%, 41%, 39%, and the upper limit of the second winglet is 58%, 56%, 54%.

In the case of exactly three winglets, the first winglet has a preferred range of 15% to 35% of the length of the chord near the split of the main wing, and the second winglet has 25% to 45%, and, The three winglets have 15% to 35%. The lower limit of the first winglet is 17%, 19%, 21%, the lower limit of the second winglet is 27%, 29%, 31%, and the lower limit of the third winglet is better. 17%, 19%, 21%. The upper limit of the first winglet is 33%, 31%, 29%, the upper limit of the second winglet is 43%, 41%, 39%, and the upper limit of the third winglet is better. 33%, 31%, 29%. The respective tip chord lengths of the winglets are preferably in the range of 40% to 100% of their respective root chord lengths, with a preferred lower limit being 45%, 50%, 55%. 60%, and the better upper limit is 95%, 90%, 85%, 80%.

Typically, these chord lengths take into account the total length available, the advantageous size distribution between the winglets, and their desired aspect ratio. Furthermore, it is desirable to optimize the airflow at a certain segment distance between the winglets in the flight direction. It can be seen from the center of the interval of the respective chord lengths that 5% to 25% (preferably at least 10%, preferably at most 20%) of the length can be used even near the roots of the winglets. The length can be used substantially entirely throughout this distance. This means that the individual chord lengths of the winglets are preferably not addable up to 100%.

Furthermore, it will be apparent to the expert that some rectifications (such as the so-called belly rectification at the transition between the base and the main wing) are used in the transition between the end of the main wing and the root of the winglets. Therefore, it is believed that the length of the chord at the end of the main wing also originates from a 10% distance from the split into many winglets (relative to the length of one half span according to one of the main wing), clearly outside the transition zone. . In the same manner, it is believed that the root chord lengths of the winglets originate from 10% outward from the split into the winglets, properly located within the appropriate wing shape of the winglets. The same applies to the position of the chord line relative to, for example, the angle of attack.

Further, in the specific example described below, the outer front corner is rounded in some of the wings and the winglets. This filleting can be accomplished by a substantial reduction in the length of the chord in the outermost portion of the winglet, but is not considered to be the aforementioned feature of the relative chord length at the tip of the winglet relative to the root of the winglet. portion. Therefore, it is mentioned here that the length of the winglet is chord length of the winglet at 10% inward of its tip end.

As previously stated, the present invention is preferably used on two wings of the same aircraft that are opposite each other. In particular, the two individual wings and winglets of the present invention on both sides may be anti-symmetric with respect to a central vertical plane in the base of the aircraft. In this sense, the invention is also relevant to the entire aircraft.

The preferred type of aircraft is the so-called transport class aircraft, which is of a certain size and should be used for the transportation of large numbers of passengers and cargo at considerable distances. Here, the economic advantage of the present invention is most satisfactory. The present invention relates to subsonic aircraft, but also to transonic aircraft, in which supersonic conditions occur particularly above the main wing and possibly above the winglet. The present invention also relates to supersonic aircraft having long-range flight speeds in the supersonic region.

Furthermore, the present invention has been conceived in view of the upgraded portion for upgrading an existing aircraft. For economic reasons, it is preferred to incorporate such an upgraded portion comprising at least two winglets on a conventional wing (or two opposing wings) rather than changing the entire wing or winglet. This is particularly sensible because the main advantage of the present invention is that it does not increase the lift of the wing that may exceed the limitations of existing mechanical structures. More specifically, the present invention preferably focuses on substantial thrust contributions to improve efficiency and/or speed. Accordingly, the present invention is also directed to such an upgraded portion and its use to upgrade an aircraft or wing in accordance with the present invention.

In both cases, the first simulation choice for the entire aircraft and for the upgrade of the existing aircraft has been the Airbus A320. Here, the outward portion of the conventional wing (a so-called fence) can be dismantled and replaced with a structure of the invention having two or three winglets.

The invention is further described in detail below with reference to the following exemplary embodiments, which are not intended to limit the scope of the claims.

1‧‧‧Aircraft

2‧‧‧ (main) wing

3‧‧‧ (main) wing

4‧‧‧Horizontal stable wing

5‧‧‧Horizontal stable wing

6‧‧‧Vertical tail

7‧‧‧body; base

8‧‧‧(first) winglet

9‧‧‧(second) winglet

10‧‧‧(third) winglet

11‧‧‧Wings

12‧‧‧Wings

13‧‧‧Chain line; (master wing) chord line

14‧‧‧ bottom line

15‧‧‧ (wing) outer end; outer wing end

16‧‧‧(airflow speed angle) maximum

17‧‧‧(outer wing end) (airflow speed angle) maximum

18‧‧‧ (middle) (airflow speed angle) maximum

20‧‧‧ (main) wing

B‧‧‧ arc shape

B‧‧‧(wing/winglet) length

B1‧‧‧(small wing) (expansion) length

B2‧‧‧(small wing) (expansion) length

B3‧‧‧(small wing) (expansion) length

Cr‧‧‧(root) (chord line) length

Cr1‧‧‧(wing string) length

Cr2‧‧‧(wing string) length

Cr3‧‧‧(wing string) length

Ct‧‧‧(tip) (chord line) length

Ct1‧‧‧(wing string) length

Ct2‧‧‧(wing string) length

Ct3‧‧‧(wing string) length

D _n ‧‧‧ resistance

F _xn ‧‧‧ thrust component

F _{xn, D} ‧‧‧ (negative) thrust component

F _{xn, L} ‧‧‧ (positive) thrust component

L‧‧‧ leading edge

L _n ‧‧‧ Lift

Ri‧‧‧radius

R1‧‧‧ radius

R2‧‧‧ radius

R‧‧‧ Root

V1‧‧‧ vertex

V2‧‧‧ vertex

W‧‧‧Wings

X‧‧‧(coordinate) axis; direction

Y‧‧‧(coordinate) axis; direction

Z‧‧‧(coordinate) axis; direction

‧‧‧‧角(度)

‧‧‧‧角(度)

γ, γ1, γ2‧‧‧ angle (degrees)

Η‧‧‧ (distance) ratio

Ε‧‧‧角(度)

δ, δ1, δ2, δ3‧‧‧ angle (degrees)

Figure 1 shows a plan view of an aircraft of the present invention comprising six schematically drawn winglets.

Figure 2 is a schematic view showing the generation of thrust by a winglet.

Figures 3a and 3b are schematic illustrations of the velocity profile of the gas flow in the tip vortex.

Figure 4 is a schematic perspective view of a wing of the present invention.

Figure 5 is a schematic front elevational view of the wing tip of the present invention including two winglets.

Fig. 6 is a graph showing two curves regarding the dependence of the tilt angle on the distance of Fig. 5.

Fig. 7 is a schematic side view for explaining a gamma angle of two winglets of a specific example.

Fig. 8 is a front view for explaining the same winglet of a δ (delta) angle.

Figure 9 is a plan view of the Airbus A320 main wing.

Figure 10 is a front view of the wing.

Figure 11 is a side view of the wing.

Fig. 12 is a side view showing a reference line used for the simulation in the specific example.

Figure 13 is a top view of the same reference line.

14 to 17 are graphs showing β(beta) angles at different distances from the tip of the main wing of the various simulations in the specific example.

Figure 18 is a front elevational view of three winglets of one embodiment of the invention showing their double sided angles.

Figure 19 is another front view of two winglets for illustrating an opposite double-sided angle.

Figure 20 is a schematic view for explaining the bending of the first winglet.

Figure 21 is a side elevational view showing a section of a main wing and three winglets at an oblique angle.

Figure 22 is a combination of a front view and a top view to illustrate the swept angle of a winglet.

Figure 23 is a top view of three winglets on one plane to illustrate the shape thereof.

Figure 24 is a perspective view of the entire aircraft of the present invention.

Figure 25 is a top view of three winglets at the tip of one of the main wing of the aircraft.

Figure 26 is a side elevational view of the three winglets of Figure 25.

Figure 27 is a front view of its three winglets.

1 is a plan view of an aircraft 1 having two main wings 2 and 3 and two horizontal stabilizing wings 4 and 5 and a vertical tail 6 and a fuselage or base 7. Figure 1 should show an Airbus A320 with four propulsion engines (not shown here). However, in Figure 1, each of the main wing 2 and 3 has three winglets 8, 9, 10, respectively. The two respective winglets of the common component symbol are mirror-symmetrical to each other in a similar manner, since the two main wing wings 2 and 3 and the base body 7 are mirror-symmetrical with respect to a vertical plane (perpendicular to the plane of the drawing) passing through the longitudinal axis of the substrate. of.

Furthermore, an x-axis opposite to the direction of flight and thus the same direction as the main airflow and a horizontal y-axis perpendicular thereto are displayed. The z-axis is vertical and upward.

Figure 2 is a wing or profile of the main wing 2 (in Figure 2, a symmetrical standard wing wing, in the case of the A320, an asymmetrical wing) and a wing that is only used to illustrate the exemplary winglet W A schematic side view of a shape (eg, a NACA 2412 standard asymmetrical wing wing or a RAE 5214 asymmetric wing wing for a sonic flight state).

The horizontal solid line is the x-axis already mentioned. The chain line 13 corresponds to the chord line of the main wing 2 (the leading point and the end point of the connection profile), and the angle α (alpha) therebetween is the angle of attack of the main wing.

Further, the bottom line 14 showing the section of the winglet W (which schematically represents one of the winglets 8, 9, 10) and the angle between the bottom line 14 and the bottom line of the main wing section are γ (so-called inclination angle) ). For the defined position of the chord line along the respective wingspan of the wing and winglet, refer to the previously described content.

Figures 3a and 3b illustrate the tip vortex present at any one of the wing tips during flight. The arrow field on the right represents the component of the airflow velocity with respect to direction and size (arrow length) on the drawing plane. Figure 3a shows the point of x = 2.5 m (x = 0 corresponds to the front end of the wing tip) and Figure 3b is for the downstream position of x = 3.4 m. It can be seen that the tip vortex "forms gradually as x increases" and that the vortex is completely concentrated around the wing tip and quickly disappears as the distance from the wing tip increases. This statement involves almost any direction from the tip of the wing, with no qualitative differences, but with small quantitative differences.

Furthermore, Figures 3a and 3b illustrate that the wing tip vortex primarily adds some of the upward component to some of the outward component of the lower region and some of the inward component of the upper region to the airflow velocity. With this in mind, it can be seen that Figure 2 shows the local airflow direction having an angle β with respect to the direction of flight x. This local airflow direction (the neglected component perpendicular to the plane of the drawing of Figure 2) impacts the symbolic winglet W and causes the lift Ln as indicated by the arrow. This lift is defined to be perpendicular to the direction of flow. It can be regarded as a superposition of the vertical upward component and the positive thrust component F _xn,L .

Most of the same applies to the resistance D _{n of the} winglet W. The resistance has a negative thrust component, ie, F _{xn, D} . The thrust contributions of the winglets W mentioned earlier in this specification are thus their difference, that is, F _xn = F _{xn, L} - F _{xn, D} , and are positive. This is the intent of the present invention, that is, the positive effective thrust contribution of the winglets.

Figure 4 shows the main wing 2 of Figure 2 and two exemplary winglets, namely, 8 and 9. The main wing 2 is slightly inclined with respect to the y-axis by a so-called sweep angle and has a chord length that decreases from the root chord length cr to the tip chord length ct with distance from the base 7. At the outer end 15 of the wing, winglets 8 and 9 are mounted, which are also in contrast to FIG.

Figure 5 shows the wing 2 and winglets 8 and 9 projected on the yz plane, and shows the length b of the main wing 2 (b is from the center of the base 7 at y = 0 along the aforementioned wingspan of the main wing 2 The respective lengths b1 and b2 of the winglets 8 and 9 are measured. For the sake of simplicity, the wing 2 and winglets 8 and 9 are only shown as straight lines and horizontal. However, no change in the qualitative direction is caused with respect to the inclination of the wing 2 about the axis parallel to the x-axis.

Figure 6 shows a graph containing two curves. The vertical axis is related to β (cf. Fig. 2), that is, the tilt angle of the local airflow direction projected on the x-z plane.

The horizontal line shows "η(eta)", that is, the distance from the outer end 15 of the wing divided by b (the length of the main wing 2).

The first curve with a cross mark is related to the absence of the winglets 8 and 9, and thus qualitatively corresponds to Figures 3a and 3b. The second curve showing the circle mark is related to the downstream of the first winglet 8, and thus to the airflow distribution upstream of the second winglet 9 (the first curve is for the same x position). These curves are generated by computer simulations of airflow distribution (eg, Figures 3a and 3b).

It can be easily seen that the first curve shows a maximum value 16 near the outer end 15 of the wing, while the second curve has a maximum value of 17 there, has an intermediate minimum at about η = 1.025, and has a value of about η = 1.055. The other maximum is 18, and it is decremented from there. Furthermore, the second curve drops to more than 50% of its smaller (left) maximum and exceeds 40% of its larger (right) maximum, while it is at approximately η = 1.1 (ie, At a distance of about 10% of the length b of the outer wing end 15) it drops to a value that still exceeds 25% of its larger maximum. Referring to Figure 2, this angular distribution is a good basis for the described function of the winglet 9.

The simulation has been based on the aircraft type Airbus A320. These simulations will be explained below. Up to now, the inventors have achieved the overall resistance of the aircraft with three winglets shown in Figure 1 by the thrust contribution of the winglet and the small increase in overall lift (within an increase of approximately 1% of the lift). Approximately 3% reduction. This increase in lift allows the aircraft to fly at a slightly lower angle of inclination (cf. a in Figure 2), resulting in a further reduction in overall drag. These simulations have been performed using ANSYS's computer program CFD (Computational Fluid Dynamics).

As a general basic study, there is a standard NACA 0012 main wing shape and a NACA 2412 winglet shape and the winglets do not have any inclination relative to the main wing (and thus have the settings of Figures 4 and 5). The computer simulation of the optimal thrust contribution of the first and second winglets has shown a good choice for the 5 series. Although higher aspect ratios are more efficient in the aerodynamic sense, they have a smaller area and thus produce less force (and therefore less thrust). In other words, within the limit of length b2 (wing span) of 1.5 m (for A320), a comparable winglet area is preferred. On the other hand, a too low aspect ratio increases the resistance, and finally reduces the effective thrust with increased resistance to reduce efficiency. In summary, the CFD simulation repeatedly shows an optimum value of about 5.

On this basis, again with reference to the settings of FIGS. 4 and 5 and the result of FIG. 6, the length b1 of the first winglet 8 upstream of the A320 is selected to be 2/3, that is, 1 m, so that the downstream second winglet 9 can Use the main part of the enlarged vortex area.

The average chord length is produced by the length of the finger wings and a fixed aspect ratio. For aircraft wings, the chord length is typically reduced toward the outer direction. For the upstream first winglet 8, the chord length at the root is 400 mm and the chord length at the tip is 300 mm, while for the downstream second winglet 9, the root chord length is 600 mm and the tip chord length It is 400mm. These values are chosen intuitively and arbitrarily.

For the winglet, instead of the above (available easily) preliminary simulation of the NACA 2412, the transonic airfoil RAE 5214 has been chosen, which is a standard transonic airfoil and is well suited for the A320 at its typical flight speed and altitude. The aerodynamic state will be compared below. The Airbus A320 is used in the documentary and economically important exemplary aircraft of the present invention.

The most influential parameters are the inclination angle γ and the double-sided angle δ (i.e., the inclination angle about the axis about the flight direction). In the first rough mapping study, the mapping step was γ of 3° to 5° and δ of 10°. In this rough map, the first and second parameters (but no third parameter) are already included in the simulation in order to have the basis of the study of the three winglets.

Figure 7 illustrates the angle γ, i.e., γ1 of the winglet 8 (first winglet) and γ2 of the winglet 9 (second winglet), both of which are shown in the shape of a wing (cf. Fig. 2), their chords The line is relative to the main wing shape and its chord line. Figure 8 illustrates the angle δ from the perspective of Figure 5, but is less schematic. Furthermore, δ1 is related to the first winglet 8, and δ2 is related to the second winglet 9. The structure in the left part of Fig. 8 is used for the instantaneous structure of the CFD simulation. These structures do not correspond to the actual A320 main wing that must be fitted with winglets (slim structures in the middle and right), but they define a practical model to implement the simulation.

Figure 9 shows a plan view of the main wing of the A320 with the wing tip down and the base body not shown, but will be above. Figure 9 shows the main wing 20 of the A320, which actually has a so-called fence structure at the end, that is, a vertical plate, which is omitted here because it will be the winglet of the present invention Replaced.

The front view of Fig. 10 shows the main wing 20, and Fig. 11 shows the main wing 20 in a side view (perspective view perpendicular to the flying side X). A slightly inclined V-shaped geometry of the main wing of the A320 can be seen in Figures 10 and 11.

A typical flight speed of Mach 0.78 and a typical flight altitude of 35,000 feet have been chosen, which represents an air density of 0.380 kg/m ³ (compared to: 1.125 kg/cm ³ on the ground), a static pressure of 23.842 Pa, 218.8 K Static temperature and actual airspeed of 450 kts (231.5 m/s). The speed chosen here is justified for the compressible simulation model compared to the uncompressed simulation model for lower speeds and thus particularly suitable for smaller passenger aircraft. This means that the pressure and temperature are variables in the gas flow, and a localized region having a gas flow velocity of 1 Mach or more (referred to as a sound transmissive flow) occurs. The total weight of the aircraft is about 70 tons. The typical angle of attack α of the main wing end of the flying shape is 1.7°. This value is depicted in Figure 2 and is related to the angle of the chord line of the main wing at its tip relative to the actual flight direction. It has been determined by this change in angle and the calculation of the overall lift obtained. When equal to the required 70, the values mentioned are roughly correct.

In this map, a parameter group (later named V0040) has been selected as the best value and serves as the basis for the next more detailed comparison.

The gamma and delta values of winglets 8 and 9 (finger wing 1 and finger wing 2) are listed in Table I. Table I shows that the first winglet 8 has a gamma angle of -10° and a -20° The δ angle (negative priority means counterclockwise rotation with respect to Figures 7 and 8), while the second winglet 9 has a gamma angle of -5° and a δ angle of -10°. From this point on, in the third and fourth columns of Table I, the gamma angle of the first winglet 8 is reduced and increased by 2°, respectively, and, in the fifth and sixth columns, the δ angle of the first winglet 8 The reduction and increase are 10° respectively. For the second winglet 9, the next four columns repeat the same schedule. For comparison, the first column has a main wing with no winglets (and no wing knives). In the row to the left of the already mentioned gamma and delta values, the analog number is listed. V0040 is the second one.

Starting from the sixth line, on the right side of the gamma and delta values, the simulation results are displayed, that is, the force in the X direction on the outer portion of the main wing in units of N (like all other forces, Newtons) ( resistance). In the seventh row, the force (lift) in the Z direction on this outer portion is displayed. This outer portion is defined starting from the boundary of the main wing tip inward by about 4.3 m. It can be used in these simulations because the outer part shows the clear influence of the winglet, while the inner part and the base do not.

The following four lines show the resistance and lift of the two winglets ("Finger Ones and Two" are the first and second winglets). Please note that the information in the first column of "Finger Wing One" is about the so-called wingtip (German: Randbogen), the structure of the wing tip between the outer interface of the main wing and the winged structure already mentioned. . This wing tip is a somewhat rounded outer wing end and is considered a "first winglet" here for a fair comparison. It can be replaced by the winglets of the present invention mounted to the same interface.

The lower row shows the overall lift/drag ratio of the wing including the outer and inner sections and the winglet (except for the first column).

The next line is the reduction in resistance ("force in the δ X direction") achieved by the two winglets in various configurations, and the respective relative values are in the penultimate row.

Finally, the relative lift/resistance ratio is shown to improve. Note that Table I includes rounding values, and calculations are done with exact values; when examining the numbers in Table I, this illustrates some minor inconsistencies.

It can be easily seen that V0040 must approximate the local optimum because the resistance reduction and the lift resistance ratio improvement of 2.72% and 6.31%, respectively, are the best results in the entire table. The small reduction in gamma of the first winglet 8 (from -10 to -8) results in a generally good result for the fourth column (V0090). The same applies to the decrease of δ from -10° to 0° of the second winglet 9, compared to V0093 of the penultimate column. Furthermore, the decrease in δ of the first winglet 8 from -20° to -30° hardly changes the result, refer to V0091. However, all other results have somewhat deteriorated significantly.

Figure 12 shows a side view as seen from the perspective of Figure 11, but with two winglets added to the main wing of Figure 11, in addition, with two stripe lines for later reference (reference line for airflow velocity angle) And Figure 13 shows a plan view of the main wing tip and two winglets having the same reference line as Figure 12. The two reference lines are 10 cm upstream of the respective leading edges of the winglets and are parallel to the leading edge.

Figure 14 is a graph corresponding to Figure 6, i.e., showing the angle β(beta) on the vertical axis and showing the distance from the tip of the main wing along the reference line just described. The basic parameter group and the simulation V0040 are indicated by a circle symbol, V0046 is represented by a triangle symbol, and V0090 is represented by a diamond symbol. The solid line is for the reference line upstream of the first winglet 8, and the dashed line is for another reference line upstream of the second winglet 9 and downstream of the first winglet 8. Table I illustrates that the first winglet 8 of V0046 has a reduced gamma angle, and that the first winglet 8 of V0090 has a gamma angle that increases the step of 2[deg.].

First, the curve shows that, as indicated by the solid line, even upstream of the first winglet 8, the first winglet 8 produces a significantly "expanded" vortex region. Compared to Figure 6, there is no significant second maximum (18 in Figure 6), but with a substantially fixed beta angle between 0.5 m and about 1.2 m. The respective lengths of the main wing are 16.35 m, which means, for example, that substantially 1.5 m has a η of 1.031, and 1.2 m has a η of 1.07 (cf. Fig. 6).

This beta value is about 9°, which is about 70% of the maximum at 0° (both apply to the reference line between the two winglets, that is, the dashed curve). Again, with a reduced gamma value, V0046 (triangle symbol) shows an increased beta upstream of the first winglet 8 and a reduced beta downstream of it. In contrast, with an increased gamma value, V0090 shows an increased beta downstream of the first winglet 8 and a reduced beta upstream of it. Therefore, with reference to Fig. 14, the inclination angle γ enhances the upward trend of the airflow between the winglets (particularly, the position within 1 m near the tip end of the main wing). In this case, the β value of 1 m or more does not deteriorate as a result. The results in Table I show that the overall performance of this parameter group is even better than V0040. This is obviously caused by a decrease in overall resistance (but the dip has been increased), that is, due to a greater contribution to the overall thrust.

On the other hand, in comparison with Table I, the decrease in the γ value from 10° to 8° (hence, from V0040 to V0046) significantly causes a large deterioration. Therefore, in a further optimization step, a higher gamma value can be analyzed, but it is not less than 10° and may even be smaller than 12°.

Again, Figure 15 shows a similar plot, but for V0040 compared to V0092 and V0091. Here, in comparison with Table I and FIG. 8, the angle δ of the first winglet 8 is changed from -20° to -10° and is changed to -30°. Obviously, this has little effect on the airflow velocity angle (β) distribution upstream of the first winglet 8 (solid line), but it has an effect on the airflow angle downstream of the first winglet 8 (dashed line). Furthermore, the value of β is increased by a little bit for a distance of 1 m or less due to an increase in the value of δ, that is, for V0091. The respective performance results in Table I are almost the same as those of V0040, and the β value in Fig. 15 is also apparently the same.

On the other hand, reducing the delta value to -10, thus aligning the two winglets side by side (as seen in the direction of flight), will qualitatively change the dashed curve in Figure 15. For values up to 1 m (i.e., the length of the first winglet 8), the beta value is reduced, and for that distance value, the beta value is significantly increased. It seems that the second winglet 9 is somewhat up to 1 m under the shelter of the first winglet 8, and "sees" the winglet tip vortex at a distance of more than 1 m. In summary, as shown in Table I, this did not improve the results, but caused some deterioration. The present invention assumes that an increase in the beta value at a distance of more than 1 m does not compensate for a decrease in beta value at a small distance.

Figure 16 shows another similar graph, now with respect to the change in the gamma angle of the second winglet 9. Again, this display does not have a large effect on the beta value upstream of the first winglet 8 (solid line), but has a significant effect on the beta value between the two winglets (dashed line). Here, the β value increases as γ decreases from 5° to 3°, and conversely, they decrease as γ increases from 5° to 7°. In a manner similar to the solid line of Figure 14, the flow into this winglet significantly reduces the angle of inclination of the airflow upstream of the winglet. The results in Table I clearly show that the two variations V0038 and V0042 reduce the performance results. In particular, the decrease in γ between the two winglets due to the increase in γ of the second winglet 9 significantly deteriorates the lift/resistance improvement. Moreover, the too large inclination of this winglet does produce more lift, but it also produces more resistance than proportionally, thus causing deterioration.

Obviously, with regard to the next optimization step, the gamma value of the downstream winglets should be kept at 5°.

Finally, Fig. 17 is about the change of the δ angle of the second winglet 9, and produces a result similar to that of Fig. 15: for V0094, the δ value of the two winglets is -20°, and further, the second winglet 9 It appears to be under the protection of the upstream winglet and shows the effect of the winglet tip vortex that would result in poorer results (especially regarding the lift resistance ratio). V0093 increases the delta difference between the two winglets without changing the delta value too much and produces similar (some improved) results in Table I. Furthermore, with regard to the next optimization step, the range of δ of the second winglet 9 between 0° and -10° is of interest.

Based on the above results, further studies were conducted on the three winglets and again based on the above description of the A320. Since the total number of possible simulations is limited, the inventors focused on what has been found for the two winglets. Therefore, based on the comparison of the resistance reduction and lift/resistance ratio of more than 2.7% of the entire wing (compared to the fourth and last penultimate rows of Table I), special considerations are given under V0040, V0090, V0091 and V0093. The parameters. As a result, simulations of different values for the dip angle γ and the double-sided angle δ are performed based on these four parameter values and evaluated in a similar manner as described above for the first and second winglets.

At the same time, information on the in-flight shape of the main wing of the A320 can be used for the main effect: the chord line at the wing end of the main wing is rotated about 1.5° from the so-called form shape under the above calculation. This can be seen by the slightly modified γ described below. Furthermore, information on the resistance of the different dip angles of the entire aircraft is available so that the overall lift improvement can be assessed (by the lift contribution of the winglets and by the limitation of losses due to vortexing). The increase in lift of the main wing) affects the overall resistance caused by changes in the inclination of the aircraft.

The results (not shown in detail here) show that the V0091 benchmark proves to be advantageous. Specific examples will be described below.

Fig. 18 shows a front view of the winglets 8, 9, 10 of this specific example seen in the x direction, and describes the double-sided angles δ1, δ2, δ3 of the three winglets. The top winglet is the first winglet, the middle winglet is the second winglet, and the lower winglet is the third downstream winglet. Figure 18 qualitatively shows that the equivalent but limited relative double-sided angle between successive winglets is confirmed to be advantageous for the particular example of the three winglets.

Taking this opportunity, Figure 19 illustrates the definition of the relative double-sided angle according to the terms of the request. At the same viewing angle as in Fig. 18, the first and second winglets are shown with two radii r1 and r2 of different sizes. The point of convergence of the vertical and horizontal lines is the root R and is the apex of the isosceles triangle shown. The other two vertices of the isosceles triangle are on the front edges of the two winglets and are referred to as V1 and V2. If an average of all radii ri in the shorter winglets (ie, the first winglet) of the two winglets is taken, the angle between the line R-V1 and the line R-V2 is the opposite double-sided angle .

The visible difference between the line R-V1 and the leading edge of the first winglet is related to the bending of the first winglet to be described below, which is also between the line of δ1 and the first winglet in Fig. 18. The far cause of deviation.

Figure 20 illustrates the bending of the first winglet described above, which can be said to be a distribution of a portion of the double-sided angle along a portion of the spanwise length. In fact, in Fig. 20, the leading edge L is schematically shown to start from the root portion R and is curved along the arc shape B, which has a radius of 750 mm and an arc angle of -15°. One third of the length (330mm). At the beginning of R, the leading edge of the first winglet has a double-sided angle of -20°. This means that the two-sided angle of the second and third portions of the length of the first winglet is actually -35°. In the average from R along the entire span length of the first winglet to its outer end, an average double sided angle of about -30 is produced by -15° along the arc "distribution".

The reason is this, in this particular embodiment, the straight leading edge of the first winglet having a double-sided angle of -30°, for providing the leading edge to the leading edge of the main wing end (in the so-called fairing area) The smooth transition of the middle is somewhat difficult, however, with a double-sided angle of -20°, the smooth transition does not cause any problems. Therefore, in order to achieve an average of -30°, the solution of Fig. 20 has been selected.

In general, the use of a winglet shape that is not straight along the spanwise direction as shown in Figure 20 is within the teachings of the present invention. They can even form an arc along the entire length as previously pointed out. The most relevant among the inventors' views is the average relative double-sided angle. If, for example, the first and second winglets are curved in a similar manner, such that the previously described isosceles triangular configuration with a fixed apex at the root is caused by the curvature of the leading edge of the winglet As the length of the equilateral increases increases, the relative double-sided angle according to this configuration may even remain almost constant along the leading edge. However, at a portion along the spanwise length of, for example, the second winglet, the nearest portion of the length along the span of the first winglet is at a relatively double sided angle (remember, the vortex at the wing end The somewhat rotationally symmetric shape) and the triangular configuration are fully described in a manner relative to the second winglet.

The absolute double-sided angles of the second and third winglets in this specific example are δ2=-10° and δ3=+10°, wherein the two winglets of this specific example do not have the arc described in FIG. shape. Therefore, the relative double-sided angle between the first and second winglets is 20°, which is the same as the relative double-sided angle between the second and third winglets, and, with reference to FIG. 18, the first winglet is second The winglet is tilted upwards and the second winglet is inclined more upward than the third winglet. The angle δ1 shown in Fig. 18 is the initial double-sided angle at the root of the first winglet, that is, -20° instead of the average of -30°.

Regarding the tilt angle, reference is made to Fig. 21, which shows a side view through a section of the three winglets 8, 9, 10 and the main wing 2. These profiles are of course different, that is, as previously described, the spanwise length of the winglets is 10% outward from the respective split position, and in the case of the main wing 2 is the inward 10 % to provide undisturbed chord lines. The chord line and the respective angles γ1, γ2, γ3 are shown in FIG. For the first winglet, the angle γ1 = -9°, for the second winglet, the angle γ2 = -4°, for the third winglet, the angle γ3 = -1°, all of which are relative to the outer position The main wing chord and the in-flight shape of the winglet and main wing (all parameters described for this particular example are related to the shape in flight) are defined.

Figure 21 also shows the respective points of rotation on the chord line of the main wing 2 and on the chord lines of the respective winglets 8, 9, 10. In terms of the length of the individual chords of the winglets, the point of rotation is approximately 1/3 of it. In terms of the length of the chord of the main wing 2, the rotation point of the first winglet is 16.7% (0% is the foremost point on the chord line), and the rotation point of the second winglet is 54.8%. At the same time, the rotation point of the third winglet is 88.1%.

Figure 22 illustrates the sweep angle ε of the representative winglet 9, i.e., the angle between its leading edge and a horizontal direction (y in Figure 22) perpendicular to the direction of flight. Here, the winglet 9 is considered to be horizontal (δ and γ are zero in the imaginary mode). Alternatively, the spanwise length of the winglet 9 can be used instead of its actual extension in the y-direction projected onto the horizontal plane. Please note that the arc of the winglet 8 described in Figure 22 will be considered unfolded. In other words, the span length includes the length of the arc.

In this embodiment, the main wing 2 has a sweep angle of 27.5°. The change from this value shows that for the winglet, an increased sweep angle of 32° is preferred, in other words, a sweep angle of 4.5° is relative to the sweep angle of the main wing. This applies to the second and third winglets 9, 10 in this particular example, however, in contrast to the top view of Figure 25 described below, for the first winglet 8, the sweep angle has been increased slightly to 34° so that Keep a certain distance to the front edge of the second winglet 9.

Figure 23 is a fictional top view of three winglets 8, 9, 10 to illustrate their shape. The reason for the fiction is that the double-sided angle and the tilt angle are zero in Fig. 23 and the arc of the first winglet 8 is unfolded. Figure 23 thus shows the respective spanwise lengths b1, b2, b3. Further showing the chord length cr1, cr2, cr3 at 10% outward of the spanwise length at the split position (these are at the bottom of Figure 23), and 10% of the spanwise inward at the tip of the winglet The tip chord length is ct1, ct2, ct3.

Actual numerical values (in order of the first winglet, second winglet and third winglet): root chord length ct of 0.4m, 0.6m, 0.4m; tip of 0.3m, 0.4m, 0.25m The chord length cr; the span length b of 1 m, 1.5 m, and 1.2 m. The root chord lengths cr respectively correspond to about 25%, about 37%, and about 25% of the length of the chord at the end of the main wing; these tip chord lengths correspond to the root chords, respectively 75%, 67%, and 63% of the length; these spanwise lengths correspond to 6.1%, 9.2%, and 7.3% of the span length (16.4m) of the main wing, respectively.

Note that the sweep angle shown in Figure 23 is not the result of the rotation run. It can be seen that the chord lengths cr and ct remain unchanged and remain in the x-z plane, in other words, on the horizontal plane in FIG. This is necessary so as not to interfere with the wing shape due to the use of the sweep angle.

Further, Fig. 23 shows the fillet of the respective outer rake angles of the shape of the winglets. This filleting system involves an area between 90% and 100% of the span length, wherein the chord length continues to reduce the chord length by 50% from 90% to 100% of the span length, so that An arc is produced in the upper view of Fig. 23. The usual practice is to use fillet at the front corners outside the wing to avoid turbulence at sharp corners. The qualitative nature of the wing shape can be maintained by the reduction of the length of the chord line within the outer 10% of the span length as just described.

The wing shape used herein is adapted to the transonic state of the A320 at the main wing at its typical flight speed and flight altitude and is designated RAE 5214. As just described, this wing shape is still effective within 10% of the span of the winglet.

Furthermore, for manufacturing and stability reasons, the trailing edge of the winglet (as opposed to the leading edge) is blunt by cutting at 98% of the length of the respective chord of all the winglets.

The transformation from the shape shown in Fig. 23 to the actual 3D geometry is as follows: First, the sweep angle shown in Fig. 23 is employed. Secondly, the first winglet has a radius of 750 mm and an angle of 15° along a bend of 1/3 of its span length. Then, the winglets are tilted by the rotation of the inclination angle γ. Then, that is, by tilting the first winglet by 20° (in addition, tilting by 15° during bending), tilting the second winglet by 10° and the third winglet by 10° downward, Adjust the double-sided angle.

Please note that the above conversion procedure is independent of the shape of the frame and the manufacturing geometry that is slightly different and depends on the elasticity of the main wing and winglet. These elastic bodies are the main body of the mechanical structure of the main wing and the winglet. This body is not part of the present invention and may vary from case to case. However, it is common practice for mechanical engineers to predict mechanical deformation under aerodynamic loads by, for example, finite element calculations. An example of an actual computer program is NASTRAN.

Therefore, depending on the actual implementation, the shape of the frame may vary, but the shape may not change during flight. Of course, the in-flight shape is responsible for the aerodynamic performance and economic advantages of the present invention.

Table II shows some quantitative results for specific examples of the three winglets just described. This is compared to A320 without the invention but with a so-called wing knife as shown in Table 1. This wing cutter is similar to the structure of the winglet, and, like the omission of the blade in Table I, is related to the improvement of the aircraft by adding the (two) winglets of the present invention to the wingless aircraft, and II shows an improvement of the present invention (i.e., a specific example of its three winglets) relative to the actual A320 including the blade cutter actually used. This is named B0001.

The lift and drag ratio (L/D) for both cases is shown in the second and third rows, and the relative improvement of the present invention is shown in the fourth row as a percentage value. This is the case for six different total masses of the aircraft between 55t and 80t, while Table I is only about 70t. The difference in quality is mainly due to the tank capacity and thus the flight distance.

Table II clearly shows that the improvement in lift and drag ratio of the present invention relative to the actual A320 is between nearly 2% in the light case and nearly 5% in the heavy case. This shows that the more effective the invention, the more pronounced the vortex produced by the main wing (in the case of heavy, the required lift is of course much larger). Compared to Table I, the improvement in lift to drag ratio is small (in Table I, the best case is about 6.3%). This is due to the positive effects of the conventional wing knives included in Table II and due to the deformation of the main wing during flight (i.e., the vortex to a certain degree of distortion of the main wing). For the typical case of 70t, the A320 including the specific example of the three winglets of the present invention has a reduced resistance compared to the conventional A320 including the wing cutter, and is currently about 4% (only the wing) and 3% (the entire aircraft). This improvement is mainly due to the thrust contribution of the second winglet and also due to the limited lift contribution of the winglet and the increased lift of the main wing by the reduction of the vortex. As previously stated, the lift contribution allows for a smaller angle of inclination of the entire aircraft in flight and can therefore be "converted" into reduced drag. The result is about 3% just described.

To illustrate, Figures 24 through 27 show the 3D shape of the A320 and the three winglets, that is, the perspective view of the entire aircraft of Figure 24, the top view of the main wing end of the Figure 25 and the winglets (toward the negative z-direction), Side view of 26 (in the y direction) and final view of Fig. 27 (in the x direction).

These figures show a smooth transition in the rectifying area between the main wing end and the winglet and also show some thickening of the inward portions of the trailing edges of the first and second winglets. These configurations are straightforward and intended to avoid turbulence.

Claims (15)

 A wing for an aircraft, the wing comprising: an outer wing end opposite to the inner side of the wing for mounting on the opposite side of the wing; at least two winglets, at The outer wing end is connected to the wing, and the first winglet upstream of the winglet is fastened in front of the second winglet downstream of the winglet in the flight direction of the wing, such as against the flight direction As can be seen, the first winglet and the second winglet are inclined to each other with respect to the opposite double-sided angles δ1, δ2 in the interval of 5° to 35°, wherein the opposite double-sided angles δ1, δ2 are defined a root of the winglets having an isosceles triangle having a vertex at its root, that is, at the splitting point of the two winglets in the horizontal direction and at the position of the leading edge of the winglets in the vertical direction In the middle, the opening angle, a vertex on the leading edge of the first winglet, and a vertex on the leading edge of the second winglet, as seen in the projection against the direction of flight, the triangle has two equal The variable length of the triangle edge, and the relative double-sided angle interval for At least 70% of the equilateral length of the shorter of the first winglet and the second winglet is effective.    The wing of claim 1, wherein the respective winglet chords are associated with each other, that is, at a distance of 10% from the length of the winglets split into the wing, Relative to the main wing chord of the wing, the length of the main wing of the wing is 10% inward from the winglets split into the wing, and the winglets are wound with the flight direction The horizontal axis of the vertical is inclined by the inclination angle γ1 of the first winglet and the inclination angle γ2 of the second winglet, and at each of the roots, the inclination angle γ1 is in the range of -15° to -5°. The inclination angle γ2 is in the range of -10° to 0°, and at its respective tip, the inclination angle γ1 is in the range of -13° to -3°, and the inclination angle γ2 is in the range of -8° to +2°. In the interval, the inclination interval is linearly interpolated between the roots of the respective winglets and the tip end, wherein, as seen from the left side of the aircraft, the positive inclination angle represents the clockwise rotation of the winglets, and the inclination angle ranges are respectively At least 70% of the length of the first winglet and the second winglet are effective.    The wing of claim 1 or 2, wherein the third winglet downstream of the second winglet, as seen against the direction of flight, the third winglet and the second winglet are at 5 The relative double-sided angles δ2, δ3 in the interval from ° to 35° are inclined to each other, wherein the opposite double-sided angles δ2, δ3 are defined as the isosceles of the isosceles triangle having a vertex at the root thereof At the root, that is, at the splitting point of the two winglets in the horizontal direction, and in the middle of the position of the leading edge of the winglets in the vertical direction, the opening angle, a vertex at the leading edge of the second winglet Above, and a vertex is on the leading edge of the third winglet, as seen in the projection against the flight direction, the triangle has a variable length of two equal triangular sides, and the opposite double-sided angle The interval is effective for at least 70% of the equilateral length along the shorter of the second winglet and the third winglet.    The wing of claim 2, wherein, optionally, in combination with claim 3, the third winglet is small for its winglet chord, that is, the length of the winglet is split into the wing The flank is 10% outward, relative to the main wing chord of the wing, where the length of the main wing of the wing is 10% from the wing that splits into the wing. It is inclined at an inclination angle γ3 around a horizontal axis perpendicular to the flight direction, and the inclination angle is in the range of -7° to +3° at the root thereof, and is -5° to +5° at the tip end thereof. In the interval, the inclination interval is linearly interpolated between the root of the third winglet and the tip of the third winglet, wherein, as seen from the left side of the aircraft, the positive inclination angle indicates the clockwise rotation of the winglet, and the The dip interval is effective for at least 70% of the span length along the third winglet.    The wing of any one of claims 1 to 4, wherein for all of the winglets, a sweep angle relative to the leading edge of the wing is between -5 and -35 relative to the wing's sweep angle. Within the interval of °, that is, reference to the average line of the leading edges of each of the winglets in the range of 20% to 80% of the wingspan of the respective winglets.    A wing according to any of the preceding claims, wherein the first winglet is inclined upward relative to the second winglet.    The wing of claim 3, wherein optionally in combination with any one of claims 4 to 6, wherein the second winglet is inclined upward relative to the third winglet.    A wing according to any one of the preceding claims, wherein the double-sided angle δ1 of the first winglet inclined with respect to the horizontal line is in the range of -45° to -15° as seen against the flight direction, The negative value of the double-sided angle indicates an upward tilt, and the respective double-sided angle δ2 of the second winglet is in the range of -25° to +5°, and, if any, the third winglet The respective double-sided angle δ3 is from -5° to +25°, wherein the double-sided angle is defined as the root of the winglet having an isosceles triangle having a vertex at its root, that is, in the horizontal direction The angle at which the splitting point of the winglets or the innermost splitting point in the case of the three winglets, and the position of the leading edge of the respective winglet in the vertical direction, a vertex at each On the front edge of the other winglet, and a vertex on the horizontal line containing the apex on the root, as seen in the projection against the flight direction, the triangle has a variable length of two equal triangle sides, and The two-sided corner sections are effective for at least 70% of the length of the equal sides along the respective winglets.    A wing according to any of the preceding claims, wherein the first winglet has a span length b1 in the interval of 2% to 10% of the length of the main wing of the wing, the second winglet Having a span length b2 in the range of 4% to 14% of the length of the main wing of the wing, and, if any, the third wing has a length on the main wing of the wing The span length b3 in the range of 3% to 11%.    A wing according to any of the preceding claims, wherein the second winglet has a spanwise length b2 in a range of 105% to 180% of the spanwise length b1 of the first winglet, and if The third winglet has a span length b3 in a range of 60% to 120% of the span length b2 of the second winglet.    A wing according to any of the preceding claims, wherein, in the case of two winglets, the first winglet and the second winglet have respective aspect ratios in the interval of 3 to 7. And wherein, in the case of three winglets, the first winglet, the second winglet and the third winglet have respective aspect ratios in the range of 4 to 9.    A wing according to any of the preceding claims, wherein, for the case of only two winglets, the root chord length cr1 of the first winglet is at the host where the winglets are split into the wing Within the range of 25% to 45% of the length of the chord, and the root chord length cr2 of the second winglet is 40% to 60 of the length of the main wing chord at the winglets split into the wing In the interval of %, for the case of three winglets, the root chord length cr1 of the first winglet is 15% to 35% of the length of the main wing chord of the winglets split into the winglets of the wing. Within the interval, the root chord length cr2 of the second winglet is within a range of 25% to 45% of the length of the main wing chord of the winglets split into the winglets of the wing, and the third winglet The root chord length cr3 is within the range of 15% to 35% of the length of the main wing chord of the winglets split into the winglets of the wing, the root chord lengths of the winglets cr1, cr2, cr3 Associated with the 10% position of the spanwise length b1, b2, b3 from the split, and the main wing chord length and the main wing span It is related to the 10% position in which the length is inward from the split.    A wing according to any of the preceding claims, wherein at the respective tips of the respective winglets, the tip chord length ct1 of the first winglet and the tip chord length of the second winglet are Ct2 and, if any, the tip chord length ct3 of the third winglet, within the range of 40% to 100% of the root chord length cr1, cr2, cr3 of the respective winglet, such small The root chord length of the wing is related to the spanwise length b1, b2, b3 of the respective winglet being split from the main wing into 10% outward from the winglet, and the tip of the winglet The chord length is related to the 10% position inward of the lengths b1, b2, b3 of the respective winglets from the tips of the respective winglets.    An aircraft, in particular a transport aircraft, having two wings of any of the foregoing claims that are opposite each other.    An upgrade portion of the use, the upgrade portion comprising at least two winglets for mounting to a wing for producing the wing of any one of claims 1 to 13 or the aircraft of claim 14.