JP5896347B2 - Hull structure and ship designed to reduce and increase resistance in waves by overflow method - Google Patents

Description

  The present invention relates to a hull structure and a ship that can reduce an increase in resistance in waves without increasing resistance in plain water.

Conventionally, for the purpose of reducing the influence of waves and reducing the viscous frictional resistance, it has been proposed to use various configurations for the hull (for example, Patent Document 1 and Patent Document 2).
Patent Document 1 discloses a configuration in which a lift plate is provided in a recess of a ship side outer plate and its upper end or lower end can protrude outward for the purpose of reducing pitching motion of the hull in waves. In addition, in Patent Document 2, for the purpose of utilizing the neck breaking wave generated at the front of the bow when the ship sails, as the microbubble of the microbubble propulsion method that reduces the viscous frictional resistance acting on the hull surface, The structure which formed the neck breaking wave conduction path under the water surface of the bow part is disclosed.

JP-A-8-11781 JP-A-9-156575

The lift plate described in Patent Document 1 is provided below the waterline for the purpose of reducing the pitching of the ship during traveling and anchoring. Moreover, the neck breaking wave conduction path described in Patent Document 2 is also provided below the water line for the purpose of utilizing microbubbles in the neck breaking wave. Thus, the structure aiming at the reduction of the influence by waves and the reduction of viscous frictional resistance is conventionally provided at a position below the sea level of the hull. However, when a configuration intended to suppress the influence of waves is provided at a position below the sea level of the hull, the configuration causes an increase in resistance in plain water (no wave).
Then, an object of this invention is to provide the hull structure and ship which can reduce the resistance increase in waves, without increasing the resistance in a plain water.

The hull structure designed to increase and reduce the resistance in waves by the overflow method according to the present invention according to claim 1 is used in a flat water where there is no wave due to the nautical speed set at the time of design as a typical speed for each ship. An overflow inlet provided only above the apex of the static water level rising position, which is a rising position of the water surface generated in the hull when traveling, an overflow outlet provided below the draft of the hull, and the overflow inlet and the overflow outlet An overflow path provided therebetween, so that at least a part of the overflow inlet faces ahead of the apex of the static water level rising position, and the overflow inlet is centered in the longitudinal direction of the hull. Set ahead of the exit center in the longitudinal direction of the hull at the exit, From low inlet incorporated through the said overflow path characterized by being discharged from the overflow outlet.
With this configuration, it is possible to take waves that have reached above the static water level rising position of the hull from the overflow inlet and discharge them from the overflow outlet. In addition, the structure in which the inlet center is positioned in front of the outlet center makes it possible to smoothly discharge water taken in as waves. Further, by providing at least a part of the overflow inlet in front of the apex of the static water level rising position, it is possible to take waves from the overflow inlet before the water level rising position in the wave reaches the apex.
According to a second aspect of the present invention, there is provided a hull structure in which the resistance in water is increased and reduced by the overflow method according to the first aspect, and the inflow resistance of the water from the overflow inlet is the reverse resistance of the water from the overflow outlet. It is characterized by being set smaller than the above.
With this configuration, it is possible to suppress the discharge of water taken in from the overflow inlet from being hindered by the backflow of water from the overflow outlet.
According to a third aspect of the present invention, there is provided a hull structure in which an increase in wave resistance is reduced by the overflow method according to the second aspect, wherein a water backflow prevention means is provided in the overflow path.
With this configuration, backflow of water in the overflow path can be prevented.
According to a fourth aspect of the present invention, there is provided a hull structure in which an increase in wave resistance is reduced by the overflow method according to one of the first to third aspects, wherein the overflow outlet is longer than the overflow inlet. It is formed in a shape, and its longitudinal direction is installed in the longitudinal direction of the hull.
With this configuration, it is possible to suppress the influence of the water discharged from the overflow outlet from the water flow at the bottom of the ship.
According to a fifth aspect of the present invention, in the hull structure in which the resistance increase in the wave is reduced by the overflow method according to any one of the first to fourth aspects, the wave rises in the vicinity of the overflow inlet. The apparatus further comprises rising wave capturing means for capturing the wave into the overflow inlet.
With this configuration, an increase in resistance due to the rising wave reaching the hull above the rising wave capturing means can be reduced. Moreover, the force which a rising wave collides can also be utilized as a thrust of a ship by a rising wave taking-in means. Here, “near” means a position where at least a part of an assumed wave rising wave can be taken into the overflow inlet by the rising wave taking-in means.
According to a sixth aspect of the present invention, there is provided a hull structure in which an increase in wave resistance is reduced by the overflow method according to one of the first to fifth aspects, wherein the overflow inlet is provided at a bow portion of the hull. Since it is the bow that is most susceptible to the influence of waves characterized by the provision of the wave, it is possible to effectively reduce the increase in resistance due to waves by providing an overflow inlet at the bow.
According to a seventh aspect of the present invention, there is provided a hull structure in which an increase in wave resistance is reduced by the overflow method according to one of the first to sixth aspects. An air supply means for supplying and controlling is further provided.
With this configuration, the gas supplied from the air supply means can be discharged from the overflow outlet and supplied to the ship bottom.
The present invention as set forth in claim 8 is a hull structure designed to increase and decrease resistance in waves by the overflow method according to one of claims 1 to 7, wherein the energy of water passing through the overflow path is reduced. An energy recovery means for recovering is further provided.
With this configuration, the energy of water passing through the overflow path can be recovered.
According to a ninth aspect of the present invention, there is provided a hull structure in which resistance increase in waves is reduced by the overflow method according to one of the first to eighth aspects. It further comprises polymer supply means for supplying a polymer.
With this configuration, water containing a high molecular weight polymer can be supplied, so that the resistance of the overflow path can be reduced and the flow of water can be made smooth.

The ship which aimed at the increase in wave resistance increase by the overflow method of the present invention according to claim 10 is a ship body which aimed at the decrease increase in wave resistance by the overflow method according to any one of claims 1 to 9. The structure is realized as a hull appendage and added to the hull.
By adding the hull structure for reducing the increase in wave resistance of the present invention to an existing ship, the increase in wave resistance of the existing ship can be reduced.
The present invention is defined in claim 11, in vessels which attained Waves increase reduces resistance by the overflow method of claim 10, range Burantonesu factor B _f is from 0.12 to 0.32 with respect to direction waves of the hull inner or Burantonesu factor B _f for countercurrent waves while adding the hull adduct is characterized in that in the range of from 0.12 to 0.32.
The hull appendage of the present invention can be attached to an existing ship without enlarging the bow shape of the hull, and the hull shape of the hull can be enlarged by attachment. Therefore, the hull Burantonesu coefficient B _f is in the range of 0.12 to 0.32, can be attached to the hull adduct as bow shape is within this range. Further, a hull appendage can be attached to a hull having a bluntness coefficient _Bf of less than 0.12 so that the bow shape is enlarged to be within a range of 0.12 to 0.32.
For example, when Burantonesu factor B _f existing vessel in the form of about 0.12 to 0.17, by adding a hull adduct, if slightly larger Burantonesu coefficients by hypertrophy bow shape of the hull The optimum value can be about 0.18 to 0.20. Thereby, the resistance resulting from the brandness coefficient of the existing ship and the increase in resistance in waves can be reduced. Also, if Burantonesu factor B _f existing vessels is 0.18 or more, bow shape so as not to bloat, by adding hull adduct, reducing the increase of wave in resistance of existing vessels be able to.

The ship which aimed at the increase in resistance in waves by the overflow method of the present invention according to claim 12 is a hull which aimed at the decrease in resistance in waves by the overflow method according to any one of claims 1 to 9. And a hull having a bluntness coefficient B _f with respect to a direction wave in a range of 0.12 to 0.32.
With range Burantonesu factor B _f for countercurrent waves described above, it is possible to improve the ship transport capacity without increase in resistance.

According to the hull structure of the present invention, it is possible to take waves that have reached above the static water level rising position of the hull from the overflow inlet and smoothly discharge them from the overflow outlet. In addition, the wave can be taken in from the overflow inlet before the water level rising position in the wave reaches the top. Therefore, it is possible to suppress the wavefront from reaching the upper part of the hull in the waves. As a result, for example, the amplitude or phase difference of the hull motion in the waves can be suppressed, and the increase in the resistance in the waves can be reduced. The same effect can be expected even in the case of various wave directions.
In the present invention, the inflow resistance of water from the overflow inlet may be set smaller than the reverse flow resistance of water from the overflow outlet. Moreover, it is good also as a structure which provided the backflow prevention means of water in the said overflow path | route. With this configuration, it is possible to smoothly capture waves from the overflow inlet, suppress backflow of water from the overflow outlet during movements where the hull sinks, and reduce the increase in resistance due to the effects of waves. Become.
In the present invention, the overflow outlet may be formed in an elongated shape than the overflow inlet, and the longitudinal direction thereof may be installed in the longitudinal direction of the hull. With this configuration, it is possible to suppress an increase in resistance due to the overflow outlet, suppress a change in the amount of drainage from the overflow outlet, and stabilize the effect of reducing the increase in resistance due to waves.
The present invention may be configured to further include rising wave capturing means. With this configuration, it is possible to reduce the increase in resistance in the waves and to use the force that the rising wave collides as the thrust of the ship by the rising wave capturing means.
In the present invention, an overflow inlet may be provided at the bow. With this configuration, it is possible to effectively reduce the increase in resistance due to waves, to smoothly discharge the taken-in water, and to rectify the flow on the hull surface.
The present invention may include air supply means. With this configuration, it is possible to realize resistance reduction by air lubrication of the overflow path itself, the hull, or both using the overflow path.
The present invention may include energy recovery means. With this configuration, for example, the backflow prevention means at the overflow outlet can be controlled using electricity generated by the recovered energy.
The present invention may include a polymer supply means. With this configuration, it is possible to reduce the resistance of the overflow path and / or the hull, to smoothly take in the waves from the overflow inlet, and to realize resistance reduction by the polymer.

  According to the ship of the present invention, it is possible to realize resistance reduction in the waves of an existing ship by the hull appendage. In addition, the hull appendage can adjust the bluntness coefficient of an existing ship and reduce the resistance caused by the bluntness coefficient of the existing ship.

  According to the ship of the present invention, resistance in plain water does not increase, and it is possible to reduce speed reduction due to waves and improve the ship's transport capability.

(A) Main part conceptual side view which shows the hull structure (example 1) by the 1st Embodiment of this invention, (b) B-B 'arrow partial sectional view Plan view showing the state of the hull viewed from above (A) The principal part conceptual side view which shows the hull structure (example 2) by the 1st Embodiment of this invention, (b) B-B 'arrow partial sectional view (A) The principal part conceptual side view which shows the hull structure (example 3) by the 1st Embodiment of this invention, (b) The principal part conceptual top view seen from the ship bottom side Graph showing the relationship between the resistance increase factor K _AW based on the reflected wave and Burantonesu coefficient B _f for countercurrent wave The principal part conceptual side view which shows the hull structure (example 4) by the 1st Embodiment of this invention The (a) principal part conceptual side view which shows the hull structure (example 1) by the 2nd Embodiment of this invention, (b) principal part conceptual front view The (a) principal part conceptual side view which shows the hull structure (example 2) by the 2nd Embodiment of this invention, (b) principal part conceptual front view The principal part conceptual side view which shows the hull structure by the 3rd Embodiment of this invention The principal part conceptual side view which shows the hull structure by the 4th Embodiment of this invention

(First embodiment)
A hull structure designed to increase and decrease resistance in waves by the overflow method according to the first embodiment of the present invention will be described below.
FIG. 1 conceptually shows the main part of the hull structure (example 1) according to the present embodiment, (a) is a conceptual side view of the main part, and (b) is the left side of the center line A ( It is a BB 'arrow partial sectional view of a), The right side is a principal part front view.
The hull structure 1 according to the present embodiment includes an overflow inlet 3 provided above the static water level rising position C of the hull 2, an overflow outlet 4 provided at a draft below the draft line D of the hull 2, an overflow inlet 3 and an overflow outlet. 4 is provided with an overflow path 5 provided between the overflow outlet 4 and water taken from the overflow inlet 3 as a wave 6 is discharged from the overflow outlet 4 via the overflow path 5.

  The overflow inlet 3 is provided so that the portion before the apex CP of the static water level rising position C is located within the range of the overflow inlet 3 in the front-rear direction of the hull 2. Further, the inlet center 3C, which is the center of the overflow inlet 3 in the front-rear direction of the hull 2, is provided so as to be positioned on the front side, that is, the bow 7 side, than the outlet center 4C which is the center of the overflow outlet 4 in the front-rear direction of the hull. Yes. Thereby, the water of the waves taken in from the overflow inlet 3 can be smoothly discharged from the overflow outlet 4.

The overflow inlet 3 takes in the waves 6 that have reached above the static water level rising position C. Thus, the overflow inlet 3 is provided above the static water level rising position C because it aims to reduce resistance in a situation where the wave 6 reaches above the static water level rising position C. By taking in the waves 6 that reach above the static water level rising position C, the movement of the hull 2 in the waves can be suppressed, and the resistance can be reduced.
If the overflow inlet 3 is provided below the static water level rising position C, water is always taken in even in plain water. For this reason, the inside of the overflow path 5 is always full, which causes the resistance to increase.
Therefore, by providing the overflow inlet 3 above the static water level rising position C, it is possible to reduce the resistance in waves without increasing the resistance in plain water. Further, the hull structure 1 of the present embodiment has an effect of reducing the resistance not only in the direction wave but also in the oblique wave.

The static water level rising position C is a rising position of the water surface that occurs when the ship travels in plain water. The marine speed is set as a typical ship speed at the time of design. The static water level rising position C refers to the rising position of the water surface that occurs when the vehicle travels in plain water at the voyage speed set for each ship.
The static water level rising position C is in a state where it rises above the waterline D, particularly at the bow portion 10, and descends smoothly and approaches the waterline D. More precisely, the static water level rising position C rises at the bow 10, then becomes lower than the draft line D, and approaches the draft line D. The magnitude of this change depends on the ship type. FIG. 1 shows an intermediate stage until the static water level rising position C approaches the draft line D and is substantially aligned with the draft line D.

  Although the static water level rising position C varies depending on the type of ship, in most ships, it is within a range of 1/4 or more and 3/4 or less of the height from the draft line D of the bow 10 to the deck. In addition, as described above, the static water level rising position C gradually becomes higher at the bow portion 10 and then becomes lower, and after matching with the water line D, it is once below the water line D and then higher again. A change from the bow 7 (front) to the stern 8 (rear) that is substantially aligned with the draft water line D is shown. Here, before the static water level rising position C substantially coincides with the water line D, the position where the static water level rising position C first coincides with the water line D after gradually increasing at the bow portion 10 is terminated. Is often in the range of 1/6 to 1/4 of the captain.

FIG. 2 is a plan view showing a state in which the hull 2 is viewed from above. In the figure, the bow 7 is located on the right side and the stern 8 is located on the left side. The hull 2 is divided into a ship side 9 having the same ship width W, a bow part 10 in which the ship width W becomes narrower as it goes to the bow 7 side, and a stern part 11 in which the ship width W becomes narrower as it goes to the stern 8 side. Can do.
Both the overflow inlet 3 and the overflow outlet 4 of the present embodiment are provided in the bow portion 10. However, the position where these are provided is not limited to the bow portion 10, and can be provided on the stern side 9, the stern portion 11, the bow 7, or the stern 8.
Further, for example, the overflow inlet 3 may be provided at the bow portion 10 and the overflow outlet 4 may be provided at the ship side or from the bow portion 10 to the ship side 9. As described above, the overflow inlet 3 and / or the overflow outlet 4 may be provided in association with a plurality of parts of the hull 2.

  The overflow outlet 4 discharges water of waves taken from the overflow inlet 3. The water in the overflow path 5 is discharged from the overflow outlet 4 by the movement of the hull 2. As shown in FIG. 1B, a backflow prevention valve 12 is provided near the overflow outlet 4 of the overflow path 5 as a backflow prevention means. In the hull structure 1 of the present embodiment, the inflow resistance of water from the overflow inlet 3 is made smaller than the reverse flow resistance of water from the overflow outlet 4 by this configuration.

  The double-headed arrow in FIG. 1 (b) indicates the vertical motion of the hull 2 when the hull 2 navigates in the waves 6, and E indicates the average position. The backflow prevention valve 12 is opened when the hull 2 moves upward from the average position E. For this reason, the water in the overflow path 5 can be discharged from the overflow outlet 4 by the potential energy of the water. Further, the backflow prevention valve 12 is closed when the hull 2 moves below the average position E. For this reason, water can be prevented from entering the overflow outlet 4 from the overflow path 5. By controlling the backflow prevention valve 12 in this way, it becomes possible to automatically discharge the water in the overflow path 5 without applying a force to the water.

Another configuration for making the inflow resistance of water from the overflow inlet 3 smaller than the reverse flow resistance of water from the overflow outlet 4 will be described below with reference to FIG.
FIG. 3 conceptually shows the main part of the hull structure (example 2) according to this embodiment, (a) is a conceptual side view of the main part, and (b) is the left side of the center line A ( It is a BB 'arrow partial sectional view of a), The right side is a principal part front view.
As shown in the figure, a phase change plate 17 may be provided in the overflow path 5 as a backflow prevention means. With this configuration, the flow of water in the overflow path 5 can easily flow from the overflow inlet 3 toward the overflow outlet 4 and can hardly flow from the overflow outlet 4 toward the overflow inlet 3. The phase change plate 17 may be either a fixed type or a movable type.

  As the backflow prevention means for preventing the backflow in the overflow path 5, in addition to the above-described check valve structure (backflow prevention valve 12) and blade (vane) structure (phase change plate 17), a simple valve structure and a control method are used. A combination etc. are mentioned. Moreover, these means can also be used in combination.

Next, a more preferable structure of the hull structure will be described with reference to FIG. FIG. 4 conceptually shows the main part of the hull structure (example 3), (a) is a conceptual side view of the main part, and (b) is a conceptual plan view of the main part viewed from the bottom of the ship. is there.
In FIG. 5A, C represents a static water level rising position, F represents a water level rising position in the waves, and F ′ represents a water level rising position when no overflow inlet is provided. And the dashed-dotted line CP has shown the position in the front-back direction of the hull 2 of the vertex of the static water level rising position C. FIG. As shown in the figure, the peak of the water level rising position F ′ in the waves is located at a position substantially similar to the vertex CP of the static water level rising position C.

In the hull 2 of FIG. 4, the overflow inlet 13 is provided in front of the apex CP at the static water level rising position C (the bow 7 side), and the overflow outlet 14 is rearward of the apex CP (the stern 8 side, FIG. 2).
By providing the overflow inlet 13 in front of the vertex CP, waves can be taken from the overflow inlet 13 before the water level rising position F ′ reaches the vertex. As a result, as schematically shown in FIG. 5A, the water level rising position F ′ indicated by the broken line is lowered to the water level rising position F indicated by the solid line. That is, due to the flow of water (downward flow) from the overflow inlet 13 to the overflow outlet 14 in the overflow path 15, the amount of increase in the water level around the hull 2 in the waves can be reduced. Thereby, it is possible to reduce the pressure received by the hull 2 in the waves and to realize a reduction in resistance.

  FIG. 4B shows a conceptual plan view of the main part viewed from the ship bottom side, and alternate long and short dash lines G and H represent the outer shape of the hull 2 at the height of alternate long and short dash lines G and H in FIG. ing. As shown in FIG. 5B, the overflow inlet 13 is provided above the water surface (above the water line D), and therefore, the outward expansion of the hull 2 is large. On the other hand, since the overflow outlet 14 is provided below the water surface (below the draft line D), the outward spread of the hull 2 is small. For this reason, the overflow inlet 13 is formed thicker and larger than the overflow outlet 14. Further, the overflow outlet 14 is formed in an elongated shape than the overflow inlet 13, and is installed so that the longitudinal direction thereof is the front-rear direction of the hull 2. Accordingly, it is possible to suppress the change in the resistance in the vicinity of the overflow outlet 14 due to the distribution of the amount of drainage discharged from the overflow outlet 14 changing in the front-rear direction of the hull 2.

The overflow outlet 14 is formed so that its cross-sectional area (cross-sectional area when cut in a horizontal plane) is larger than the cross-sectional area of the overflow inlet 13. Thereby, the water taken in from the overflow inlet 13 can be smoothly discharged from the overflow outlet 14. Therefore, water can flow smoothly without collecting in the overflow path 15, and the waves 6 can be smoothly taken in from the overflow inlet 13.
Further, since the overflow outlet 14 is installed such that the longitudinal direction thereof is the front-rear direction of the hull 2, an increase in resistance due to the overflow outlet 14 itself can be suppressed as compared with the case where the overflow outlet 14 is installed in the lateral direction.

FIG. 5 is a graph showing the relationship between the bluntness coefficient B _f for the directional wave and the resistance increase coefficient K _AW based on the reflected wave. As shown in the figure, in the range where the bluntness coefficient _Bf is 0.187 or less, the resistance increasing coefficient once reaches a peak at the bluntness coefficient 0.12, and then decreases to 0.187. When the bluntness coefficient is 0.187 or more, the resistance increase coefficient increases in proportion to the bluntness coefficient. In this proportional range, when the bluntness coefficient is 0.32, the resistance increase coefficient is approximately the same value as 0.12. For this reason, by setting the bluntness coefficient of the hull 2 within the range of 0.12 to 0.32, the transport capability of the ship can be improved without increasing the resistance. If the hull 2 has a shape with a bluntness coefficient of about 0.12 to 0.17, the shape of the bow 10 of the hull 2 may be enlarged to slightly increase the bluntness coefficient to about 0.18 to 0.20. preferable. With this configuration, it is possible to simultaneously realize a decrease in the resistance increase coefficient and an improvement in the transport capability.

The Burantonesu coefficient B _f, a factor affecting the resistance increase coefficient K _AW based on the reflected wave is a coefficient representing the enlargement degree on the water surface in the hull 2. The relationship between the resistance increase coefficient K _AW and the bluntness coefficient B _f is expressed by the following formula (1) together with α ₁ : draft effect term and speed effect term (1 + α ₂ ).
K _AW = B _f · α ₁ · (1 + α ₂ ) (1)
B _f : Brandtness coefficient α ₁ : Drafting influence term (1 + α ₂ ): Speed influence term

  FIG. 6 is a conceptual side view of the main part showing the hull structure (example 4) according to the present embodiment. As shown in the figure, an energy recovery means 16 for recovering the energy of water passing through the overflow path 15 may be provided. As a result, the energy of the water flow in the overflow path 15 can be recovered and generated. Examples of the energy recovery means 16 include a device that converts a water flow into a rotational motion, such as an impeller or a propeller. The electricity obtained from the energy recovery means 16 can be used, for example, to supplement the energy for operating the check valve 12 provided at the overflow outlet 14.

(Second Embodiment)
A second embodiment of the present invention will be described below with reference to FIGS. The hull structure of the present embodiment is different from the above-described embodiment in that an overflow inlet is provided in the stem portion. Members having the same functions as those described in the above-described embodiments are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 7 conceptually shows the main part of the hull structure (example 1) according to this embodiment, (a) is a conceptual side view of the main part, and (b) is a front view of the main part. As shown in the figure, the overflow inlet 23 is provided in a stem portion that is a ridge line portion of the bow 7 of the hull 22. For this reason, in the waves, the waves 6 near the bow 7 can be taken into the overflow inlet 23, so that the rise of the water level can be suppressed and the resistance received by the hull 22 can be suppressed.

FIG. 8 conceptually shows the main part of the hull structure (example 2) according to the present embodiment, (a) is a conceptual side view of the main part, and (b) is a front view of the main part. . In the figure, a configuration is shown in which an ascending wave capturing means 24 for capturing the rising wave of the wave 6 into the overflow inlet 23 is provided in the vicinity of the overflow inlet 23.
By providing the rising wave capturing means 24, an increase in resistance due to the rising wave reaching the hull above the rising wave capturing means can be reduced. In addition, the force applied to the rising wave capturing means 24 when the rising wave collides can also be used as the thrust.

  The ascending wave capturing means 24 includes a surface facing the overflow inlet 23 configured such that the front (bow 7) side is lower than the rear (stern 8) side. Therefore, the force applied to the rising wave capturing means 24 by the waves 6 can be used as the propulsive force of the hull 22 as shown by the white arrow surrounded by the thick line in FIG.

  In the present embodiment, the configuration in which the rising wave capturing means 24 that covers the overflow inlet 23 is provided integrally with the hull 22 has been described. However, the rising wave capturing means 24 is not limited to this, and may be configured as a bowl-shaped addition or step that is not integral with the hull. Moreover, it is good also as attaching to the overflow entrance attached except the stem part.

(Third embodiment)
A third embodiment of the present invention will be described below with reference to FIG. The hull structure of the present embodiment is different from the above-described embodiment in that an air supply means for supplying gas or supplying and controlling gas is provided in the overflow path. Members having the same functions as those described in the above-described embodiments are denoted by the same reference numerals, and description thereof is omitted.

FIG. 9 is a conceptual side view showing a main part of the hull structure according to the present embodiment. FIG. 9A shows the hull structure 31 provided with the bubble outlet 33, and FIG. The hull structure 32 provided with the bubble generating device 34 is shown.
By providing the bubble flow outlet 33 and / or the bubble generator 34 in the overflow path 5, the bubbles can reach the overflow outlet 4 at the bottom of the ship using the flow of water. In this way, by using the downward flow of the overflow path 5, it is possible to save the power for sending the bubble flow to the bottom of the ship, and to realize resistance reduction by gas lubrication.

  By flowing the bubbles to the bottom of the ship in this way, not only the resistance of the overflow path 5 but also the resistance of the hull can be reduced. Moreover, when the bubble flow outlet 33 and / or the bubble generator 34 are provided in the vicinity of the overflow outlet 4, the resistance of the hull can be mainly reduced.

  As a means for supplying to the overflow path 5 or supplying and controlling the gas by the bubble flow outlet 33 and the bubble generating device 34, for example, a device that takes in air by a blower or a pump, or a compressed air of a supercharger is used. And those that generate bubbles by the gas-liquid shearing method. Here, the gas-liquid shearing method refers to a method of generating bubbles by creating a vortex, entraining gas therein, and cutting and crushing the gas with an impeller or vane.

(Fourth embodiment)
A fourth embodiment of the present invention will be described below with reference to FIG. The hull structure of the present embodiment is different from the above-described embodiment in that a polymer supply means for supplying a polymer to water passing through the overflow path is provided. Members having the same functions as those described in the above-described embodiments are denoted by the same reference numerals, and description thereof is omitted.

FIG. 10 is a conceptual side view of the main part showing the hull structure 41 according to the present embodiment. As shown in the figure, the hull structure 41 is provided with a polymer supply means 42 in the vicinity of the overflow inlet 3 of the overflow path 5. By supplying the polymer to the water taken in from the overflow inlet 3 by the polymer supply means 42, the frictional resistance of the water flowing through the overflow path 5 can be reduced (Toms effect).
The Toms effect can reduce the frictional resistance by up to 70%. For this reason, the flow of water from the overflow inlet 3 to the overflow outlet 4 is made smooth, and the efficiency of taking in the waves 6 (see FIG. 1) from the overflow inlet 3 is improved.

  As the polymer supply means 42, for example, a structure in which a polymer release hole for releasing a small amount of polymer polymer is provided, or a part or front part of the overflow path 5 is painted with a polymer elution paint to dissolve the polymer. A configuration in which a high molecular weight polymer is eluted from the paint can be considered.

  By supplying the polymer from the polymer supply means 42, not only the resistance of the overflow path 5 but also the resistance of the hull can be reduced. Moreover, when the polymer supply means 42 is provided in the vicinity of the overflow outlet 4, the resistance of the hull can be mainly reduced.

  The hull structure of each embodiment mentioned above can also be added to the hull of the existing ship as a hull appendage. This makes it possible to reduce the resistance of existing ships in the waves.

  The present invention can be widely applied to ships such as container ships, oil tankers, LNG ships, and LPG ships. Further, the hull structure of the present invention can be provided at the time of construction of a ship, or can be provided later on an existing ship.

1,21,31,32,41 Hull structure 2,22,42 Hull 3,13,23 Overflow inlet 3C Inlet center 4,14 Overflow outlet 4C Outlet center 5,15 Overflow path 6 Wave 10 Bow 12 Backflow prevention valve ( Backflow prevention means)
16 Energy recovery means 17 Phase change plate (backflow prevention means)
24 Ascending wave capturing means 33 Bubble outlet (air supply means)
34 Bubble generator (air supply means)
43 Polymer supply means C Static water level rising position CP vertex (vertical water level rising position vertex)
D water line W ship width

Claims (12)

Provided only above the apex of the static water level rising position, which is the rising position of the water surface generated in the hull when traveling in flat water where there is no wave due to the sailing speed set at the time of design as a representative speed for each ship Overflow inlet,
An overflow outlet provided below the draft of the hull;
An overflow path provided between the overflow inlet and the overflow outlet, wherein at least a part of the overflow inlet faces forward of the top of the static water level rising position, and the hull of the overflow inlet The overflow center is set forward of the center of the overflow outlet in the longitudinal direction of the hull, the wave is taken in from the overflow inlet and discharged from the overflow outlet through the overflow path. A hull structure designed to reduce and increase resistance in waves by using this method.   The hull structure according to claim 1, wherein an inflow resistance of water from the overflow inlet is set smaller than a reverse resistance of water from the overflow outlet.   3. A hull structure for increasing and reducing resistance in waves by the overflow method according to claim 2, wherein means for preventing backflow of water is provided in the overflow path.   The overflow method according to any one of claims 1 to 3, wherein the overflow outlet is formed in an elongated shape than the overflow inlet, and a longitudinal direction thereof is set in a longitudinal direction of the hull. A hull structure designed to reduce resistance in waves.   5. The overflow method according to claim 1, further comprising rising wave capturing means for capturing the rising wave of the waves into the overflow inlet in the vicinity of the overflow inlet. 6. A hull structure designed to reduce resistance in waves.   6. A hull structure for reducing an increase in resistance in waves by an overflow method according to claim 1, wherein the overflow inlet is provided at a bow portion of the hull.   7. An increase in resistance in waves by the overflow method according to claim 1, further comprising gas supply means for supplying gas or supplying and controlling gas to the overflow path. The hull structure.   8. An increase in wave resistance is reduced by the overflow method according to claim 1, further comprising energy recovery means for recovering energy of water passing through the overflow path. 10. Hull structure.   The resistance increase in waves by the overflow method according to any one of claims 1 to 8, further comprising polymer supply means for supplying a polymer to water passing through the overflow path. The hull structure.   10. The resistance in waves by the overflow method, characterized in that the hull structure for reducing and increasing resistance in waves by the overflow method according to claim 1 is realized as a hull appendage and added to the hull. Ships designed to increase and decrease.   The bluntness coefficient Bf for the direction wave of the hull is within the range of 0.12 to 0.32, or the bluntness coefficient Bf for the direction wave with the hull appendage added is within the range of 0.12 to 0.32. The ship which aimed at the resistance increase increase in the waves by the overflow system of Claim 10 characterized by the above-mentioned. It has a hull structure that aims to reduce resistance increase in waves by the overflow method according to one of claims 1 to 9,
A ship designed to reduce an increase in resistance in waves by an overflow method, comprising a hull having a bluntness coefficient Bf with respect to a direction wave in a range of 0.12 to 0.32.