CN112722260B - An adaptive drum bag lifting device - Google Patents

Abstract

The invention relates to a self-adaptive bulge high-lift device, belonging to the technical field of aviation aircrafts; the ducted propeller comprises a ducted propeller, a flexible skin, a sliding rail, a rolling bearing and a side vertical plate; the two side vertical plates are oppositely arranged in parallel and are vertically fixed at the tail part of the aircraft body of the aircraft; the inner walls of the two side vertical plates are provided with a group of slide rails, and each group of slide rails comprises two rails which are used as the motion trail of the ducted propeller; the bottom surface of the ducted propeller is connected with the fuselage of the aircraft through a flexible skin, and the flexible skin deforms along with the movement of the ducted propeller. Through pneumatic verification calculation, the lift increasing effect is 10% of the thrust. When the aircraft enters a cruising stage, the thrust is reduced, the duct inlet descends under the action of self gravity, the flexible skin moves towards the direction far away from the aircraft body, the flexible skin is straightened, the calculation result shows that the aerodynamic characteristics of the aircraft in a cruising state are not affected, and the self-adaptive bulge high-lift device is simple in structure, low in cost and easy to realize.

Description

An adaptive drum bag lifting device

technical field

The invention belongs to the technical field of aeronautical aircraft, and in particular relates to a self-adaptive bulge-enhancing device.

Background technique

The main difference between a VTOL/STOL aircraft and a conventional aircraft is that it can not only fly like a conventional aircraft, but also perform aerial hovering, vertical landing, acceleration/deceleration transition, side shift and vertical/short takeoff, etc. These special functions make vertical/short-range aircraft more survivable than conventional aircraft in narrow venues or harsh climatic conditions, so it has become one of the development directions of future aircraft.

The way of VTOL/STOL aircraft to achieve VTOL has gone through the process of aircraft steering to engine steering and then to thrust steering. The configuration design of the propulsion system of modern VTOL aircraft is based on the concept of thrust steering. Can be summarized as: integrated propulsion system, combined propulsion system and composite propulsion system.

Taking the tilting ducted vertical/short takeoff and landing aircraft as the research object, a ducted fan is arranged at the tail of the aircraft, and the thrust steering is realized by the tilting of the ducted fan, so as to further achieve the function of vertical/short takeoff and landing. However, this method of tilting the ducted fan also has obvious shortcomings. There is a geometric gap between the duct inlet and the fuselage, which does not achieve smooth and continuous deformation, and destroys the flow field at the duct inlet.

Therefore, it is urgent for researchers in this field to further optimize the design of the propulsion system of the existing vertical/short take-off and landing aircraft to solve the problem of the geometric gap between the entrance of the tilting duct and the fuselage, so as to improve the efficiency of the propulsion system technical issues.

SUMMARY OF THE INVENTION

Technical problem to be solved:

In order to avoid the deficiencies of the prior art, the present invention proposes an adaptive bulge-enhancing device, which further optimizes the design of the propulsion system of the existing vertical/short take-off and landing aircraft for the above-mentioned proposals, so as to meet the requirements of vertical/short Under the condition of taking off and landing, the working efficiency of the propulsion system is improved, and the present invention provides an adaptive bulge increasing device. The device can not only improve the working efficiency of the aircraft in the take-off stage, but also ensure that the aircraft has high aerodynamic characteristics in the cruising state.

The technical scheme of the present invention is: an adaptive bulging lifting device, which is characterized in that: it includes a ducted propeller, a flexible skin, a sliding rail, a rolling bearing and a side vertical plate; the two side vertical plates are arranged in parallel and opposite to each other, and are vertically fixed at the rear of the fuselage of the aircraft; the inner walls of the two side uprights are provided with a set of slide rails, and each set of slide rails includes two rails, which are used as the motion trajectory of the ducted propeller;

The ducted propeller is an integrated structure composed of a plurality of ducted power units arranged in parallel, and a first rotating shaft and a second rotating shaft are vertically arranged above the outer walls on both sides of the ducted propeller. The two rails are installed together and can be tilted relative to the fuselage; the first rail is set horizontally, corresponding to the first rotating shaft near the end of the ducted propeller outlet, as the movement path of the first rotating shaft; The second rotating shaft at one end of the inlet of the ducted propeller corresponds to the movement path of the second rotating shaft;

The bottom surface of the ducted propeller is connected to the fuselage of the aircraft through a flexible skin, and the flexible skin is deformed with the movement of the ducted propeller.

The further technical scheme of the present invention is: the first track and the second track of the sliding rail are both straight tracks, and the track length and the oblique upward angle are calculated as follows:

涵道螺旋桨轴线的角度分别为θ^a、θ^b；设所述滚动轴承的安装点在起飞阶段位置为

巡航阶段位置为

则：After aerodynamic calculation, the center of gravity of the aircraft is taken as the origin, and the direction of the nose is the x-axis to establish a coordinate system. During the take-off and cruise phases of the aircraft, the positions of the center of gravity of the ducted propellers are:

The angles of the ducted propeller axis are θ ^a and θ ^b respectively; the installation point of the rolling bearing is set to be at the take-off stage

The cruise phase position is

but:

与

和

与

之间的相对关系一定，根据上述方程组，解算出特定位置下起飞阶段与巡航阶段的滚动轴承安装点位置，即为所述两条滑轨的起点与终点，进而得到轨道的长度和斜向上角度。Since the rolling bearing is installed on the shaft of the ducted propeller, the

and

and

and

The relative relationship between them is certain. According to the above equations, the position of the rolling bearing installation point in the take-off stage and the cruise stage at a specific position is solved, which is the starting point and end point of the two slide rails, and then the length of the rail and the oblique upward angle are obtained. .

A further technical solution of the present invention is: the length of the flexible skin is limited: when the aircraft takes off, the arc segment formed by the extrusion of the flexible skin is tangent to the lower surface of the ducted propeller.

A further technical solution of the present invention is that: the flexible skin is made of carbon fiber.

beneficial effect

The beneficial effect of the present invention is that: the self-adaptive bulge-enhancing device of the present invention can be used as an elevating device for a propulsion system of a vertical/short take-off and landing aircraft, driving the ducted propeller to tilt to realize vertical/short take-off and landing. At the same time as the lowering function, the ducted propeller translates along its own axis. During the take-off and landing stage, the thrust of the ducted propeller itself is greatly increased, and the ducted propeller is pulled to move along the slide rail, the ducted entrance is lifted, and at the same time, it moves along the ducted axial direction toward the nose, and the distance from the fuselage is reduced. The lift of the duct entrance makes the thrust direction turn to achieve the purpose of vertical/short take-off and landing. The distance between the ducted propeller and the fuselage is reduced, and the flexible skin between the ducted propeller and the fuselage is squeezed, and the length of the flexible skin is designed so that the arc segment formed by extrusion and the ducted propeller The lower surface is tangent to improve the flow field at the inlet of the ducted propeller. After aerodynamic verification and calculation, the lifting effect is 10% of the thrust. When the aircraft enters the cruise stage, the thrust decreases, and the duct entrance descends under the action of its own gravity, and moves away from the fuselage at the same time, and the flexible skin is straightened. The calculation results show that the aerodynamic characteristics of the aircraft in the cruise state are not In addition, the self-adaptive bulge lifting device is simple in structure, low in cost and easy to implement.

Description of drawings

Figure 1 is a schematic diagram of the stop/cruise state of the self-adaptive bulge-enhancing device;

Fig. 2 is a schematic diagram of the take-off state of the self-adaptive bulge-enhancing device;

Fig. 3 is the azimuth schematic diagram of the self-adaptive bulge increasing device;

Reference numeral description: 1 is the fuselage, 2 is the ducted propeller, 3 is the flexible skin, 4 is the sliding rail, 5 is the rolling bearing, and 6 is the side vertical plate.

Detailed ways

The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to explain the present invention and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", " rear, left, right, vertical, horizontal, top, bottom, inside, outside, clockwise, counterclockwise, etc., or The positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, Therefore, it should not be construed as a limitation of the present invention.

As shown in FIG. 1 and FIG. 2 , an adaptive bulging lifting device includes a fuselage 1 , a ducted propeller 2 , a flexible skin 3 , a slide rail 4 , a rolling bearing 5 , and a side vertical plate 6 .

The ducted propeller 2 is located in the rear section of the aircraft, as the main power component of the vertical/short take-off and landing aircraft, and has a degree of freedom of movement relative to the fuselage 1 .

Both ends of the carbon fiber flexible skin 3 are respectively consolidated with the fuselage 1 and the ducted propeller 2 , and are deformed with the movement of the ducted propeller 2 .

The sliding rail 4 is composed of two straight rails, which are installed on the side vertical plate 6. The side vertical plate 6 is located outside the ducted propeller and is fixedly connected with the fuselage. The track at the entrance is an inclined upward track, and the position of the center of gravity of the duct and the direction of the axis are determined by the positions of the front and rear bearings. The specific length of the track and the upward angle of the slope are determined by the position of the ducted propeller during the take-off and landing and cruise phases.

涵道螺旋桨轴线的角度分别为θ^a、θ^b；设所述滚动轴承的安装点在起飞阶段位置为

巡航阶段位置为

则：Assuming that through aerodynamic calculation, the center of gravity of the aircraft is the origin, and the direction of the nose is the x-axis to establish a coordinate system. During the take-off and cruise phases of the aircraft, the positions of the center of gravity of the ducted propellers are

The angles of the ducted propeller axis are θ ^a and θ ^b respectively; the installation point of the rolling bearing is set to be at the take-off stage

The cruise phase position is

but:

与

和

与

之间的相对关系一定，联立上述方程组，可以解算出特定位置下起飞阶段与巡航阶段的滚动轴承安装点位置，即为所述两条滑轨的起点与终点。Since the rolling bearing is mounted on the ducted propeller, the

and

and

and

The relative relationship between them is certain. By combining the above equations, the position of the rolling bearing installation point in the take-off stage and the cruise stage at a specific position can be calculated, that is, the starting point and the end point of the two slide rails.

The rolling bearings are located on both sides of the ducted propeller, are fixedly connected with the ducted propeller, and are restricted to move in the slide rail to reduce the influence of friction on the movement of the ducted propeller.

As shown in Figure 1, in the shutdown/cruising state, the angle of the ducted propeller 2 relative to the fuselage 1 is small or even horizontal, and the two ends of the flexible material 3 are respectively fixed to the lower surface of the fuselage 1 and the entrance of the ducted propeller 2 , the fuselage 1 and the ducted propeller 2 are in a straight state to ensure that the aircraft has high aerodynamic characteristics in the cruising state.

To make the aircraft enter the take-off state, the thrust of the ducted propeller 2 needs to be greatly increased, and the great increase of the thrust can pull the ducted propeller 2 to move relative to the fuselage.

Due to the existence of the slide rail 4 and the rolling bearing 5, the ducted propeller 2 will move according to a predetermined trajectory.

Further, the movement of the ducted propeller 2 will drive one end of the flexible material 3 fixed on its lower surface to move.

Since the other end of the flexible material 3 is fixedly connected with the fuselage 1, the movement of one end will compress the flexible material to cause bending deformation, thereby forming a bulge.

Through the design of parameters such as the relative position of the ducted propeller and the fuselage, the trajectory of the ducted propeller, and the length of the flexible material, the bulge of the flexible material 3 is tangent to its lower surface at the fixed connection with the ducted propeller 2, so as to improve the culvert. The flow field distribution at the inlet of the ducted propeller will further increase the lift and improve the working efficiency of the propulsion system including the ducted propeller and flexible materials.

When the take-off action is completed, reduce the throttle to reduce the thrust of the ducted propeller 2, and use the self-weight of the ducted propeller 2 to slide it down to the position in the stop/cruise state along the designed motion trajectory. At this time, the flexible material 3 will once again It is straightened, combined with the movement of the ducted propeller 2 under high thrust, so as to realize the adaptive function of the bulging and lifting device.

Although the embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and those of ordinary skill in the art will not depart from the principles and spirit of the present invention Variations, modifications, substitutions, and alterations to the above-described embodiments are possible within the scope of the present invention without departing from the scope of the present invention.

Claims (2)

1. The utility model provides a self-adaptation swell high lift device which characterized in that: the ducted propeller comprises a ducted propeller, a flexible skin, a sliding rail, a rolling bearing and a side vertical plate; the two side vertical plates are oppositely arranged in parallel and are vertically fixed at the tail part of the aircraft body; the inner walls of the two side vertical plates are provided with a group of sliding rails, and each group of sliding rails comprises two rails which are used as the motion trail of the ducted propeller;

the ducted propeller is an integrated structure consisting of a plurality of ducted power units arranged in parallel, a first rotating shaft and a second rotating shaft are vertically arranged above the outer walls of the two sides of the ducted propeller, and each rotating shaft is respectively matched and installed with the two rails of the sliding rails on the two sides through a rolling bearing and can tilt relative to the aircraft body; the first track is horizontally arranged, corresponds to the first rotating shaft close to one end of the ducted propeller outlet and serves as a moving path of the first rotating shaft; the second track is obliquely and upwards arranged, corresponds to a second rotating shaft close to one end of the inlet of the ducted propeller and is used as a moving path of the second rotating shaft;

the bottom surface of the ducted propeller is connected with a fuselage of the aircraft through a flexible skin, and the flexible skin deforms along with the movement of the ducted propeller;

the first track and the second track of the slide rail are both straight tracks, and the length and the inclined upward angle of the tracks are calculated as follows:

through pneumatic calculation, a coordinate system is established by taking the gravity center of the aircraft as an origin and the nose direction as an x axis, and the gravity center positions of the ducted propellers of the aircraft are respectively at the take-off stage and the cruise stage

The angles of the axes of the ducted propellers are theta ^a 、θ ^b (ii) a The position of the mounting point of the rolling bearing at the take-off stage is set as

The cruising stage position is

Then:

since the rolling bearing is mounted on the rotating shaft of the ducted propeller, the rolling bearing is mounted on the rotating shaft of the ducted propeller

And

the relative relation between the track and the track is fixed, and the positions of the rolling bearing mounting points in the specific take-off stage and the cruise stage at specific positions are solved according to the equation set, namely the starting point and the end point of the track, so that the length and the inclined upward angle of the track are obtained;

the flexible skin length defines: when the aircraft is in a take-off state, the arc line segment formed by extrusion of the flexible skin is tangent to the lower surface of the ducted propeller.

2. The adaptive bump-height increasing device of claim 1, wherein: the flexible skin is made of carbon fiber.

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