JP2009299650A - Straightening fluid wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems wherein efficiency is reduced because in the past, a tip vortex or stalling easily occurs around a blade when workload is taken out using a windmill or a water wheel or thrust is provided using a screw or a propeller. <P>SOLUTION: A blade tip straightening plate is provided for connecting the blade end of a rotating blade for preventing stalling of a blade tip or noise and loss due to a blade tip vortex. Thereby, it is possible to suppress the blade tip stalling or a vortex or the like around the blade. In addition, the blade tip straightening plate has a fly wheel function, thereby it is possible to reduce torque fluctuations. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a technique for improving the efficiency of obtaining propulsive force by extracting energy from a fluid by a windmill, a water wheel, a screw, or a propeller (hereinafter collectively referred to as a “fluid wheel”) or by supplying energy to a propulsion shaft.

Conventionally, fluid vehicles have been used for wind power generation, hydroelectric power generation (hereinafter collectively referred to as “fluid power generation”), grinding and pumping water, or for propulsion of ships and aircraft.
At this time, many efforts have been made to improve the efficiency of how much energy can be extracted from a fluid having a constant flow velocity or how much driving force can be obtained from the constant energy.

For example, in a propeller type fluid vehicle, it is needless to say that generating the higher torque is the most effective means to increase the efficiency if the fluid velocity is the same strength to extract the energy from the fluid with high efficiency. Absent.

Torque is the rotational axis (hereinafter referred to as “revolution axis”) of the rotor blade (hereinafter simply referred to as “wing”) of the fluid vehicle.
That's it. ) And the lift product acting in the direction of rotation generated by the blade at that point, the chord length is increased toward the blade tip (hereinafter referred to as “inverted taper blade”), and the tip lift force is increased. A measure to improve the torque by increasing the torque is to use a wing.

On the other hand, however, the common problem with fluid wheels with any hydrodynamic power feature is that noise and efficiency decrease due to vortices that are likely to occur at the tip of the blade, or streamlines peel off from the blade surface, and the lift of the blade is reduced. The phenomenon of disappearing (hereinafter referred to as “stall”) is also likely to occur at the blade tip.
The stall generated at the blade tip (hereinafter referred to as “blade tip stall”) easily spreads over the entire blade.

In order to prevent these and to improve the strength of the wing, it is made thinner (the chord length of the wing cross section is shortened) toward the tip of the wing (hereinafter referred to as “taper wing”), and measures such as rounding the tip are taken. It has been.

Furthermore, in order to prevent blade tip stall, the angle of attack was reduced at the tip of the blade (hereinafter referred to as “wing tip twist down”).

What is the reason why reverse tapered wings to gain torque and tapered wings to prevent stalling, or the seemingly opposite measures such as rounded tips and twisting down of the wing tips are taken?

Inverted taper blades are prone to blade tip stalls, so it was not possible to obtain a sufficient angle of attack. Blade tip vortices were also likely to be generated, and noise and loss were major issues.

In order to produce high torque, there was no method other than improving the aerodynamic characteristics of the tip of the wing in order to achieve both a reverse-tapered wing and a characteristic that resists stalling, or increasing the overall length of the wing to improve the torque.

The wings generate lift because the front and back have different flow velocities and the dynamic pressure acting on the surface is different, but there is no blade tip between the positive pressure part on the front and the negative pressure part on the back. Passing through, the fluid in the positive pressure part on the front surface goes around to the negative pressure part on the rear surface, and the streamline in contact with the rear surface is peeled off from the blade surface, resulting in blade tip stall.

In order to prevent this, as a barrier that prevents the movement of the fluid that moves from the front surface of the blade to the back surface of the blade, the propeller type fluid vehicle has a thin plate 2 (hereinafter referred to as “wing blade”) perpendicular to the surface of the blade 1 as shown in FIG. There is a method of adding an end straightening plate ”to the blade tip.

In vertical axis type fluid wheels, the position of the tip of the wing is changed from side to side to prevent the wing coming from behind from being cut off by the interference caused by the vortex generated at the front wing tip. As shown, a contrivance has been made such as providing a wing tip current plate.

Even in a fluid vehicle using blades equipped with blade tip rectifying plates, the blade tip rectifying plates themselves also generate vortices and turbulence (hereinafter referred to as “turbulent flow”) around the front and rear edges. The noise and loss have not been completely removed.

In addition to increasing the size of the wing and increasing its cost, the method of increasing the torque by increasing the overall length of the wing requires the strength of the wing so that it is difficult to adopt a reverse-tapered wing that generates large torque. The problem was not solved.

Next, in hydroelectric power generation and the like, a particular problem is torque fluctuation due to the strength of the fluid velocity.

This has a great influence on the overall efficiency as a fluctuation that is very difficult to handle because of fluctuations in power and frequency as output.

As a countermeasure, a method of adding a heavy object (hereinafter referred to as “flywheel”) for increasing the rotational inertia to the tip of the blade as shown in FIG. 5 is considered. It may also cause fluid turbulence.

The first invention of this application is a fluid vehicle in which a blade tip rectifying plate is provided so as to connect the blade tips of the rotor blades.

According to a second aspect of the present invention, in the propeller type fluid wheel, the blade tip rectifying plate is provided such that the tip of the blade is connected to a cylindrical blade tip rectifying plate. It is a fluid vehicle.

The third invention of the present application is characterized in that the blade tip rectifying plate is provided such that the tip of the wing is connected to a disk-shaped or concentric disk-shaped blade tip rectifying plate when the fluid wheel is a vertical axis type fluid wheel. The fluid vehicle according to claim 1.

A fourth aspect of the present invention is the fluid vehicle according to any one of claims 1 to 3, wherein the blade tip rectifier plate has a flywheel function provided on the blade tip rectifier plate.

The fluid wheel of the present invention refers to the use of rotor blades to extract energy from the fluid flow, such as windmills and water turbines, or the use of rotor blades to provide energy to propelling force using propellers and screws. Is a general term for devices that generate

Since the wind turbine and the water turbine, the propeller, and the screw are different only in whether the torque is obtained by the lift and drag generated in the rotor blades or the thrust is obtained, the operation for obtaining the torque will be described below.

As a result of studying whether there is a method for solving the above problems, the inventors have reached the following invention.

Since vortices and turbulence are also generated around the leading and trailing edges of the blade tip rectifying plate, as shown in FIG. 3, in the propeller type fluid wheel, the blade tip rectifying plate is in contact with the tip of the blade and the rotation axis of the fluid wheel is the center. By providing a cylindrical blade tip rectifying plate connected to the shaft, it is possible to eliminate the leading and trailing edges of the blade rectifying plate 3 itself. (Claim 2)

For the same reason, as shown in FIG. 4, in the vertical shaft type fluid wheel, the blade tip rectifying plate is formed into a disk shape 4A or a concentric disk shape 4B with the rotation center of the fluid wheel in contact with the tip of the blade as a central axis. The edges and trailing edges can be eliminated. (Claim 3)

Further, by increasing the weight of the connected blade tip rectifying plates 6A, 6B and 6C shown in FIG. 6, it is possible to have a flywheel function and eliminate the front and rear edges. (Claim 4)

In the propeller type fluid wheel, the front and rear edges of the rectifying plate are eliminated by making the wing tip rectifying plate into a cylindrical shape connecting the tip of the wing, so the noise and loss due to the surrounding vortex on the rectifying plate can be reduced. It is possible to prevent blade tip stalls more reliably, so it is possible to use reverse tapered blades that produce high torque. (Claim 2)

In a vertical shaft type fluid vehicle, the front and rear edges of the rectifying plate are eliminated by making the wing tip rectifying plate into a disk or concentric disk that connects the wing tips. The noise and loss due to can be reduced, and the blade tip stall can be prevented more reliably. It can also prevent the wings that rotate in the rear from getting involved in the turbulent flow. (Claim 3)

By adding flywheel function to the connected vane tip rectifier plate in a fluid vehicle, the rotational inertia can be increased without increasing the fluid resistance of the fluid vehicle as a whole, and the generation and loss of turbulence can be suppressed. . (Claim 4)

The front view, perspective view, and side view of a propeller type fluid wheel provided with a wing tip current plate. The perspective view of the vertical axis type fluid wheel provided with the wing tip current plate. The front view, perspective view, and side view of a propeller type fluid wheel provided with a cylindrical wing tip current plate. The perspective view of the vertical axis | shaft type fluid wheel provided with the disk shape and the concentric disk shape wing tip rectifier. The front view of a propeller type fluid vehicle provided with a flywheel, a perspective view, and the perspective view of a vertical axis type fluid vehicle. Front view, perspective view, and side view of a propeller type fluid vehicle with a flywheel function on a cylindrical blade tip rectifier The perspective view of the vertical axis | shaft type fluid wheel which gave the flywheel function to the disk shape and the concentric disk shape wing tip rectifying plate. Comparison diagram.

Explanation of symbols

1 wing 2 wing tip rectifier plate 3 cylindrical wing tip rectifier plate 4A disc wing tip rectifier plate 4B concentric disk wing tip rectifier plate 5 flywheel 6A cylindrical wing tip rectifier plate flywheel 6B disc wing tip rectifier plate flywheel 6C Concentric disk-shaped rectifier flywheel

Claims (4)

  In the fluid vehicle, the fluid vehicle is provided with a blade tip rectifying plate so as to connect the blade tips of the rotary blades. 2. The fluid wheel according to claim 1, wherein the blade tip rectifying plate is provided such that a tip of the blade is connected to a cylindrical blade tip rectifying plate when the fluid wheel is a propeller type fluid wheel. 2. The fluid wheel according to claim 1, wherein the blade tip rectifying plate is provided with a disk-shaped or concentric disk-shaped blade tip rectifying plate connected to the tip of the blade in a vertical shaft type fluid wheel. . The fluid vehicle according to claim 1, wherein the blade tip rectifying plate has a flywheel function.

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