RU2459974C1 - Wave electric power station - Google Patents

Abstract

FIELD: power industry.

SUBSTANCE: wave electric power station includes fixed support 1, pneumatic hydraulic chamber 2 the underwater part of which is interconnected through open lower edge 3 with water reservoir, and above-water part is interconnected with atmosphere through pressure air line 6 fixed on upper edge 5 of chamber 2. Turbine 7 with blades 8 of wind-type profile is installed across air line 6. Turbine 7 is kinematically connected to generator 9 installed on upper edge 5 of chamber 2. On opposite inner surfaces of air line 6 there made are projections with concave walls. Projections adjoin cylindrical surface swept with blades with a gap. On support 1 there arranged is rotating actuator 15 kinematically connected to chamber 2 which is fixed on support 1 with possibility of vertical movement in compliance with oscillations of medium level of water surface.

EFFECT: higher efficiency of wave electric power station.

7 cl, 5 dwg

Description

Technical field

The invention relates to hydropower and can be used to absorb wave energy in water areas characterized by significant level fluctuations, for example, due to tidal, tidal, surging or seasonal phenomena.

State of the art

Wave power plants (VolNES) are characterized by a wide variety of operating principles and design solutions [see, for example, RU 2347940, IPC F03B 13/24, 2007; RU 2351793, IPC F03B 13/22, 2007; RU 77362, IPC F03B 13/22, 2008; RU 2388933, IPC F03B 13/16, 2008].

The proposed device relates to a wave power plant with preliminary conversion of wave energy into energy of the air flow. The conversion is carried out using a pneumohydraulic chamber, the underwater part of which is connected to the reservoir, and the surface part is connected to the atmosphere through the pressure duct. The air flow rotates a turbine installed in the duct, kinematically connected with the electric power generator.

Technical and economic calculations show that the use of powerful waveguides of this type is economically feasible with an average (for example, daily) efficiency of at least 0.6.

The main losses in such VolNES are associated with the conversion of the energy of the air flow into the energy of rotation of the turbine installed in the duct, and with the loss of energy in the pneumohydraulic chamber. In water areas characterized by significant changes in the level of the water surface, the efficiency (its average value) of known waveguides of this type drops additionally precisely due to an increase in energy losses in the pneumohydraulic chamber.

This is because changes in the level of the water surface of the water area are accompanied by displacements of the water-air boundary in a stationary pneumohydraulic chamber and changes in the immersion depth of the chamber relative to the optimal positions adopted during design. If the camera is immersed too deep, its efficiency decreases, and if the immersion is too shallow, there is a risk of exposing the lower end of the camera with a loss of operability of the device.

Known wave power plant containing a pneumatic hydraulic chamber mounted on a floating support with a smooth-walled pressure duct (in the form of a dome), in which an orthogonal air turbine with wing-shaped blades is installed [patent RU 77362, IPC F03B 13/22 from 2008]. The support is made in the form of a vertically floating pipe. The lower part of the pipe is perpendicular and rigidly bonded to a plate with high hydrodynamic resistance and submerged to a depth of at least half the wavelength. The floating support is fixed in the required place of the water area using ropes and anchors.

Experimental studies have shown that the efficiency of an orthogonal turbine in a smooth-walled pressure duct does not exceed 0.35.

In addition, the known device is unsuitable for construction and operation as part of or in conjunction with coastal protection structures, dams, dams of tidal power plants, i.e. in conditions that significantly increase the technical and economic indicators of VolNES.

Known as a prototype is a wave power plant containing a pneumatic-hydraulic chamber mounted on a fixed support with a pressure duct, in which an Wells axial turbine with wing-shaped blades is installed. The axis of the Wells turbine is oriented along the air stream. A generator is mounted on a turbine axis in a duct [Proceedings of fourth European wave energy conference, Aalborg, Denmark, December 2000, fig. 3. A.F. de O. FALCAO "The shoreline OWC wave power plant at the Azores"].

Experimental studies have shown that the efficiency of the Wells turbine in an alternating-direction air stream does not exceed 0.5. The generator installed in the duct further reduces the efficiency of the prototype.

The disadvantage of the prototype is low energy efficiency, especially in areas characterized by significant changes in the average level of the water surface.

The objective of the invention is to remedy this drawback.

Disclosure of invention

The subject of the invention is a wave power plant comprising a fixed support, a pneumohydraulic chamber, the underwater part of which is connected to the reservoir, and the surface part with the atmosphere through a pressure duct fixed to the upper end of the chamber, at least one turbine with wing-shaped blades crosswise installed, kinematically associated with the generator, while on opposite inner surfaces of the pressure duct for each turbine there are protrusions with concave walls adjacent to the gap m to the cylindrical surface swept by the blades of the turbine, and on the support there is a rotating drive kinematically connected to the camera, which is mounted on the support with the possibility of vertical movement in accordance with fluctuations in the average level of the water surface.

The technical result of the invention is to increase the efficiency of VolNES operating in water areas with a changing level of the water surface to an economically feasible value at which the average efficiency is at least 0.6.

The invention has developments related to particular cases of its implementation and consisting in the fact that:

- the rotary drive is kinematically connected with the pneumatic chamber through a pair of power elements from a number of nuts - a screw, a gear - a gear rack, a hydraulic cylinder - a rod, a drum - a cable;

- the fixed support and the pneumohydraulic chamber are provided with guides;

- the rotary drive is equipped with automatic control with the ability to move the camera relative to the support in accordance with fluctuations in the average level of the water surface;

- the generator is installed on the upper end of the pneumohydraulic chamber outside the pressure duct;

- the support is made in the form of a vertical rack mounted on the foundation, and the pneumohydraulic chamber is equipped with an internal pipe covering the support;

- the support is hollow with the possibility of temporary sealing and transportation by floating method to the place of its installation.

Brief Description of the Drawings

Figure 1 shows a wave power plant in which a pneumohydraulic chamber is mounted on a massive fixed support with the possibility of vertical movement along one of its walls.

Figure 2 shows a section bB (see figure 1), illustrating the design of a pressure duct with a turbine.

Figure 3 shows a section bb (see figure 1), illustrating the design of the rails mounted on the support and the camera.

Figure 4 presents the node A (see figure 1) to illustrate the possible implementation of the kinematic connection between the drive mounted on the support and the pneumohydraulic chamber moving along it.

Figure 5 shows a wave power plant in which the support is made in the form of a vertical rack mounted on the foundation, and the camera moves along the support using an internal pipe enclosing the support.

The implementation of the invention in view of its developments

The wave power station contains (see Fig. 1) a fixed support 1 and a pneumohydraulic chamber 2 mounted on it. The underwater part of the chamber 2 is communicated through the open bottom end 3 with a reservoir, and the surface part with the atmosphere through the hole 4 and fixed on the upper end 5 of the chamber 2 pressure duct 6. A turbine 7 with blades 8 of a wing-shaped profile is installed across the duct 6 (shown in FIG. 2). The turbine 7 is kinematically connected (for example, by a common shaft) with a generator 9 installed outside the duct 6. On the opposite inner surfaces of the duct 6 in the alignment of the turbine 7 there are protrusions 10 with concave walls 11 and 12 (see figure 2). The protrusions 10 are adjacent with a gap δ to the cylindrical surface 13 swept by the blades 8.

It is possible to install several turbines 7 across the air duct 6, for each of which a pair of protrusions must be made 10. In this case, the turbines can be kinematically connected each with its own generator or with one generator common to them.

The camera 2 is mounted on a support 1 with the possibility of vertical movement. In this case, along with the chamber 2, the air duct 6 with the turbine 7 and the generator 9 are mounted on the upper end 5 of the chamber 2.

Figure 1 shows that the generator 9 is installed on the upper end 5 of the chamber 2 using auxiliary support. It is also possible to install the generator 9 using an auxiliary bracket mounted on the duct 6.

The support 1 and the camera 2 moving relative to it can be provided with guide elements 14 (see Figs. 1 and 3).

A rotary drive (engine) 15 is placed on the support 1, which is kinematically connected to the chamber 2 through a pair of power elements from a number of nuts - a screw, a gear - a gear rack, a hydraulic cylinder - a rod, a drum - a cable. In figures 1, 4 and 5, an example shows the use of a pair of nuts 16, enclosed in a housing 17, and a screw 18. The nut 16 (see figure 4) is connected to the shaft of the rotary actuator 15 through a conical pair, and the screw 18 is connected with camera 2.

The actuator 15 may be equipped with control means that enable automatic movement of the chamber 2 relative to the support 1 in accordance with fluctuations in the level of the water area (reservoir).

The support 1 can be made hollow with the possibility of temporary sealing and transportation by floating method to the place of its installation.

The support can be made (see Fig. 5) in the form of a vertical rack 20 installed on the foundation 19. In this case, the chamber 2 is provided with an inner pipe 21 covering the rack 20. Anchor devices can also be used to increase the stability of the support.

To improve the technical and economic indicators of the VolNES, shown in Fig. 1, it can be performed as part of or together with shore protection structures, dams, dams of tidal power plants, the elements of which can be used as supports. The VolNES support can also be attached to a steep, for example rocky, shore.

Wave power plant operates as follows.

The water surface 22 separates the chamber 2 into the air cavity 23 and the water cavity 24. The cavity 23 is connected to the atmosphere through the opening 4 and the pressure duct 6. In the absence of wind waves or when the shutter shutter 25 of the duct 6 is closed, there is no air movement through the turbine 7.

The reservoir in which the power plant is being built, as a rule, is an area of the sea or ocean in which waves appear under the influence of wind.

The appearance of waves is accompanied by vertical oscillations of the surface 22, the corresponding oscillatory changes in the volume of the air cavity 23 and pressure pulsations in the inlet cavity of the duct 6 adjacent to the hole 4. The air is alternately pushed through the duct 6 into the atmosphere and sucked back. The air flow rate can be considered inversely proportional to the cross-sectional area of the flow (at the pressures and velocities acting in this case, air compressibility can be neglected). Since the cross-sectional area of the chamber 2 is much larger than the cross-sectional area of the turbine alignment of the duct 6, the speed of the air flow through the turbine 7 is many times higher than the speed of air movement in the cavity 23 caused by vibrations of the surface 22.

The turbine 7 with blades 8 of a pterygoid profile (see figure 2) is a transverse-jet orthogonal turbine. The profile of each blade 8 is similar to the profile of an airplane wing and has blunt and sharp ends. The blade 8 has respectively a blunt and sharp edge.

The air flow of a variable direction, which is formed in the air duct 6 during oscillations of the surface 22, having reached a certain minimum speed, drives the turbine 7. The rotational force acts in the direction of the blunt faces of the blades 8, regardless of the direction of the air flow.

When the turbine 7 rotates, the blades 8 sweep an imaginary cylindrical surface 13 with their extreme points from the axis of rotation, to which the transverse protrusions 10 having concave walls 11 and 12 adjoin with a gap δ and the protrusions 10 with concave walls 11 and 12 perform the function wall guide apparatus, providing optimal angles of attack of the rotating pterygoid blades 8 with respect to the incoming air flow.

The use of a transverse orthogonal turbine 7 (instead of the Wells axial turbine in the prototype) allowed the generator 9 to be removed from the air stream, placed above the water level, and thereby improve its operating conditions.

The generator 9, kinematically connected with the turbine 7, generates electricity during its rotation. The higher the speed of the turbine and generator, the more power can be given to the consumer. As the generator 9, it is advisable to use an alternating current generator in conjunction with a frequency converter.

The amplitude of the vertical vibrations of the water surface 22 inside the chamber 2 and the power of the air flow in the duct 6 decrease when the end face 3 of the chamber 2 is too deeply immersed in water due to a decrease in the amplitude of pressure pulsations at the end face 3 from waves on the surface of the water near the chamber 2, and if it is too shallow When diving, the end face 3 is exposed with atmospheric air entering through it into the cavity 23, which in both cases leads to a decrease in the efficiency of the pneumohydraulic chamber.

In tidal or tidal events, the average level of the surface 22 and the depth of immersion of the butt 3 change in accordance with changes in the level of the water surface of the water area. In order to ensure that the depth of immersion in the water of the end face 3 of the chamber 2 remains within the required limits, the chamber 2 is mounted on the support 1 with the possibility of vertical movement.

The movement is carried out on additionally installed rails 14 (see figures 1 and 3) or without them. In the structure shown in FIG. 5, the rails 20 and the pipe 21 serve as guides.

The drive 15 located on the support 1, by means of which the camera 2 moves, can be, for example, electric or gasoline. Its rotational movement provides vertical movement of the chamber 2 using a pair of power elements that convert the rotational movement of the actuator 15 into translational. Figures 1, 4 and 5 show, by way of example, designs using a pair of nut-screw power elements.

Nut 16 (see figure 4) is installed in the housing 17, rigidly mounted on the support 1, using two radial 26 and two thrust 27 rolling bearings. The nut 16 rotates the bevel gear wheel 28 fixed on it by means of a gear 29 mounted on the rotary shaft of the drive 15. The rotation of the nut 16 imparts translational motion to the screw 18 connected to the chamber 2 by the extension rod 30 (see FIGS. 1 and 5).

Automation of the drive 15 controls the movement of the chamber 2 (for example, using a float - level sensor), providing the required immersion of the end face 3 in accordance with changes in the surface level of the reservoir.

This ensures practical immobility of the chamber 2 with respect to the rapid wave oscillations of the surface 22, necessary for the efficient use of wave energy, and the vertical movement of the chamber 2 in accordance with the relatively slow changes in the average level of the surface 22 caused by tidal and tidal effects.

The experimentally confirmed efficiency of the proposed VolNES with optimal immersion of chamber 2 lies within 0.63-0.68, and the calculated average daily efficiency of such a VolNES at the designed Northern tidal-wave power station in the Dolgaya Bay of the Barents Sea was at least 0.6.

The proposed design of a wave power plant is suitable for the most efficient floating method of construction in the open sea. This method involves the manufacture of support 1 in the form of a hollow reinforced concrete structure and the assembly of a power plant in a factory. The assembled power plant with air filled and sealed support 1 is towed afloat to the place of its construction. If necessary, auxiliary pontoons installed under the chamber 2 in the embodiment of the support structure in FIG. 5 can also be used for transportation.

At the construction site, the power plant is immersed, as a rule, on a natural underwater base by filling the support 1 or pontoons with ballast water. After that, the water ballast inside the support 1 in figure 1 can be replaced by a heavier ballast, for example, sand and gravel soil. Stability at the bottom of the pond of the support, made in the form of a stand 20 (see Fig. 5), can be achieved due to the massive foundation 19 and ballast transported with it, as well as due to the streamlined cylindrical shape of the stand 20 and chamber 2, which reduces the impact on them storm waves.

The support of the wave power plant in the form of a floating block facilitates and reduces the cost of its construction.

Claims (7)

1. A wave power plant containing a fixed support, a pneumohydraulic chamber, the underwater part of which is connected with the reservoir, and the surface part is connected to the atmosphere through a pressure duct fixed to the upper end of the chamber, through which at least one turbine is installed with wing-shaped blades kinematically connected with a generator, while on opposite inner surfaces of the pressure duct for each turbine there are protrusions with concave walls adjacent with a gap to the cylindrical surface , Swept blades of the turbine, and is placed on a support rotary drive kinematically associated with a camera which is fixed on a support with the possibility of vertical movement in accordance with fluctuations in the average level of the water surface. 2. The wave power plant according to claim 1, characterized in that the rotary drive is kinematically connected to the camera through a pair of power elements from a number of nuts - a screw, a gear - a gear rack, a hydraulic cylinder - a rod, a drum - a cable. 3. The wave power plant according to claim 1, characterized in that the fixed support and the pneumohydraulic chamber are provided with guides. 4. The wave power plant according to claim 4, characterized in that the rotary drive is equipped with automatic control with the ability to move the camera relative to the support in accordance with fluctuations in the average level of the water surface. 5. The wave power plant according to claim 1, characterized in that the generator is installed on the upper end of the pneumohydraulic chamber outside the pressure duct. 6. The wave power plant according to claim 1, characterized in that the support is made in the form of a vertical rack mounted on the foundation, and the pneumohydraulic chamber is equipped with an inner pipe covering the support. 7. Wave power plant according to any one of claims 1 to 6, characterized in that the support is hollow with the possibility of temporary sealing and transportation by floating method to the installation site.

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