JPH0620185U - Device for improving water separation performance of hydrofoil - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a water separation performance improving device capable of blowing air from the bottom of a ship at the time of takeoff to prevent a pressure drop at the bottom of the ship and achieving a smooth transition to a wing running state. [Structure] A large number of compressed air outlets 4 communicating with outside seawater are arranged on the bottom of a hydrofoil 1, and air pipes 5 and 6 equipped with a compressed air supply source 7 are connected to the outlets 4. In this structure, another air pipe 11 whose one end is open to the atmosphere is added to the air pipe 6.
The other end of is connected via the on-off valve 12.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 This invention aims to improve the take-off (water separation) performance of such hydrofoil vessels by blowing air from the bottom of the boat to make the bottom pressure equal to or higher than atmospheric pressure when the boat is switched from wing to wing (take-off). Regarding the device.

[0002]

[Prior art]

Recently, a hydrofoil 1 as shown in Fig. 4 has appeared on domestic routes, which should meet the needs for high-speed transportation of passengers and cargo. The hydrofoil ship 1 has a strut 2 hanging from the bottom of the ship in the front and rear, and a hydrofoil 3 at the lower end of each strut 2. Then, at low speed, the boat sails with the water-driving WL ₁ , and at high speed, the lift of the hydrofoil 3 moves the bottom of the ship away from the surface of the water and floats up to the water-driving line WL ₂ to sail in the wing-running state. The propulsion method is water jet propulsion. In such a hydrofoil, the most propulsive force is required when taking off, and the horsepower of the main engine that should obtain the necessary thrust at this time is set.

[0003]

[Problems to be solved by the device]

 The lift of the hull of a hydrofoil increases as the speed increases, and the hull rises, and the bottom pressure decreases at the take-off when the bottom separates from the water surface (water separation). At this time, the force to be pulled downward becomes large, which causes a large horsepower to be required at the time of takeoff. Therefore, the current situation is to equip this with a main engine that is larger than necessary for the required horsepower at cruising speed. However, equipping a large main engine does not meet the demand for weight reduction, which is particularly important for such ships. Thus, in the past, this was dealt with by increasing the horsepower of the main engine, but due to the problem of pump cavitation, a satisfactory effect was not always obtained. It is desirable for smooth operation of the hydrofoil vessel to take off and enter the wing state in a short period of time, but it is hard to say that this has been achieved by the conventional vessels.

An object of the present invention is to provide a take-off performance improving device capable of blowing air from the bottom of a ship at the time of take-off to eliminate a pressure drop at the bottom of the ship and achieving a smooth transition to a wing running state. .

[0005]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a hydrofoil vessel that takes off by the lift of hydrofoil at high speed to wing and is provided with a plurality of compressed air outlets communicating with outside seawater at the bottom of the hydrofoil vessel. A water separation performance improving device for a hydrofoil, characterized in that an air pipe provided with a compressed air supply source is connected to the air outlet, and in this configuration, the air pipe has a separate end opened to the atmosphere. The water separation performance improving device for a hydrofoil, characterized in that the other end of the air pipe is connected via an on-off valve.

[0006]

[Action]

 In the above configuration, compressed air is supplied from the air pipe to the outlet, blows out from the bottom of the outlet, and the pressure at the bottom is reduced at the time of take-off by making the pressure at least at the bottom equal to atmospheric pressure. It prevents the ship from spilling and weakens the force that the bottom of the ship is pulled downward. In this case, the compressed air may be positively blown out from the blowout port, or the negative pressure generated at the bottom of the ship can be prevented by connecting the air pipe, one end of which communicates with the atmosphere, to the outside of the ship's bottom. You may do it.

[0007]

【Example】

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective side view of a hydrofoil to which the present invention is applied. Fig. 2 is a view of the main parts of the air outlet provided on the bottom of the ship. 3 (a) and 3 (b) show another embodiment. As shown in FIG. 1, a hydrofoil 1 has struts 2 hanging from the bottom near the bow and stern of the hydrofoil, and hydrofoils 3 are provided at the lower ends of the struts 2. As mentioned above, at low speeds, the boat runs on the waterline WL ₁ , and at high speeds, the lift of hydrofoils moves the bottom of the boat away from the surface of the water, and the hull floats up to the waterline WL ₂ and runs. The propulsion system is so-called water jet propulsion, in which water is jetted by a water jet pump provided in the stern hull to obtain thrust.

As shown in FIGS. 1 and 2, a large number of compressed air outlets 4 are arranged in the center of the bottom of the hydrofoil 1 along the lengthwise direction of the bottom. The outlet 4 communicates from the bottom of the ship to the outside. An air pipe 6 branched from a main compressed air pipe 5 is connected to each of these outlets 4, and the main compressed air pipe 5 is connected to a compressed air supply source 7 and an accumulator 8 and a solenoid valve 9 in the middle. Connected. On the other hand, an air intake device 10 such as a mushroom type ventilator is provided on the deck of the hydrofoil 1, and an air pipe 11 having one end open to the atmosphere is connected to the air pipe 6 through an on-off valve 12. It is connected. The air pipe 11 may be an independent pipe without being connected to the main compressed air pipe 5. Therefore, a negative pressure is applied to the bottom of the ship by positively ejecting the compressed air supplied from the compressed air supply source 7 from the outlet 4 or by simply communicating the outside of the ship with the atmosphere via the air pipe 11. You may not want to become.

As shown in FIGS. 3 (a) and 3 (b), an air box 13 of a predetermined size is provided in the ship length direction of the ship bottom, and the air pipe 5A is connected to one or two places of the air box 13, and A large number of blowout openings 14 are opened on the bottom of the ship in the range of the air box 13 to blow air from the air box 13 to form a wide range of air layers on the bottom of the ship to more effectively prevent the bottom pressure drop. The water separation resistance may be reduced as much as possible.

The operation of the device of the present invention will now be described. It is assumed that the hydrofoil sails on WL ₁ on the waterline, and eventually becomes high speed, and the lift of hydrofoil 3 increases, and it is now time to take off. At this time, the solenoid valve 9 is opened by the ship speed (or before the pressure is detected by the pressure sensor provided at the bottom of the ship and the pressure becomes negative), and compressed air is instantaneously supplied from the accumulator 8 to the air pipe 5, Supply to each outlet 4 through 6. Then, the compressed air is jetted from the outlet 4 to the water surface outside the ship bottom.

By this, the negative pressure on the bottom of the ship is avoided, the pulling force on the bottom of the ship is weakened, and the take-off can be performed smoothly.

Instead of the above method, the solenoid valve 9 is kept closed, and the opening / closing valve 12 is opened so that the outside of the ship bottom and the atmosphere can communicate with each other via the air pipe 11. Eventually, also in this case, the air from the atmosphere is blown out from the blowout opening 14, the drop in the bottom pressure is prevented, and the takeoff is smoothly performed.

Further, in the case of the embodiment of FIGS. 3A and 3B, if compressed air is constantly supplied and filled so that water does not enter the air box 13, the air is blown out from the blowout opening 14. In addition, an air layer is formed near the bottom of the ship, which not only reduces the frictional resistance of the hull, but also effectively prevents the decrease in the bottom pressure.

[0014]

[Advantage of the Invention] By blowing air from the bottom of the boat through the air pipe during the transition from take-off to take-off (take-off), the bottom pressure becomes at least equal to atmospheric pressure, and the bottom pulls downward. As a result, the take-off performance can be improved. The device of the present invention assists the lift of the hydrofoil at the time of takeoff, and as a result, the takeoff can be smoothed and the horsepower of the main engine can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective side view of a hydrofoil to which the present invention is applied.

FIG. 2 is a state diagram in which air is blown out from an outlet.

3 (a) and 3 (b) are a cross-sectional view showing another embodiment of an air blowing opening and a bottom view of a ship bottom.

FIG. 4 is a side view of a hydrofoil of an application example of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Hydrofoil 2 ... Strut 3 ... Hydrofoil 4 ... Outlet 5 ... Main compressed air pipe 6 ... Air pipe 7 ... Compressed air supply source 8 ... Accumulator 9 ... Solenoid valve 10 ... Air intake device 11 ... Air pipe 12 ... Open / close valve 13 ... Air box 14 ... Blowout opening

Claims (2)

[Scope of utility model registration request] 1. In a hydrofoil ship that takes off by the lift of a hydrofoil at high speed to fly, a plurality of blowout ports for compressed air communicating with outside seawater are provided at the bottom of the hydrofoil boat, and the blowout ports are provided at the blowout ports. An apparatus for improving the water separation performance of a hydrofoil, characterized in that an air pipe equipped with a compressed air supply source is connected. 2. The water separation performance of a hydrofoil ship according to claim 1, wherein another end of the air pipe having one end open to the atmosphere is connected to the air pipe according to claim 1 through an on-off valve. Improvement equipment.