CN113175406B - Parent fish type through-flow turbine - Google Patents

Abstract

The invention discloses a ichthyophile type tubular water turbine, the flow area of which includes a water inlet room, a guide vane area, a runner area with spiral blades, a water outlet pipe diffusion section and an extension section connected in sequence, and the water inlet room has a cross section of Square, guide vane profile is positive curvature crescent, runner blades are helical blades, and the ratio of the initial pitch of the helical blade to the cut-off pitch is 1:5, and the ratio of the length of the diffuser section of the outlet pipe to the length of the extension section of the outlet pipe is 1: 4. The invention aims at improving the survival rate of machine-passing fish under the premise of ensuring the hydraulic performance of the water turbine, has broad application prospects and popularization value, and is of great significance to the coordinated development of hydropower energy utilization and ecological environment.

Description

A fish-breeding type tubular water turbine

technical field

The invention belongs to the technical field of hydraulic machinery, in particular to a fish-loving type tubular water turbine.

Background technique

The energy problem has become one of the main bottlenecks in the development of countries in the world, and the use of new energy to meet the future energy incremental demand is a practical and inevitable choice for all countries. my country's ocean energy is rich in reserves, widely distributed, clean and pollution-free, and the main way of development and utilization is power generation, among which tidal power generation and small wave power generation technologies have been put into practical use. Ocean energy power generation has made a significant contribution to alleviating my country's energy crisis and reducing global environmental pollution, but the hydraulic machinery that uses ocean energy to generate electricity has a certain impact on the ecological environment. For tidal power generation, a fish-friendly water turbine has been developed, which uses water level difference to generate electricity, aiming to improve the survival rate of passing fish while ensuring the hydraulic performance of the water turbine.

As we all know, with the vigorous development of hydropower energy, water conservancy and hydropower projects have had a certain impact on the ecosystem of water areas. For example, the impact of reservoir power stations on the ecological environment of the original river water, and the flow-through components such as water turbines cause additional deaths and injuries to fish passing through the machine. The construction of the dam divides the original ecosystem into discontinuous ecological zones, which seriously hinders the migration of fish and may cause a devastating blow to the reproduction of migratory fish. Many hydroelectric power stations in the Columbia River Basin in the United States have successfully solved the problem of salmon migration by building new fish shafts or fish ladders. In addition, some foreign hydropower stations use surface fishways to assist fish to pass down the machine. The principle of the above method is to use fish Due to the swimming characteristics of the surface of the water body, an auxiliary shaft channel is set on the surface of the inlet of the turbine inlet to guide the fish into the auxiliary channel to ensure the safety of the fish passing through the machine. Many large-scale water conservancy projects in my country have also taken corresponding measures in the process of design, planning and construction. By building barrier facilities such as fishways, fish elevators and fish gates, fish will not pass through the water turbine when they descend. Although the above measures have achieved certain results, on the one hand, the construction cost is high and the efficiency is low, and a large number of fish are inevitably sucked into the turbine and injured; on the other hand, the internal flow of the turbine is equivalent to multiphase flow with solids, which is different from the ideal state The utilization rate of flow field is lower than that of water.

In addition, most of the existing fish-breeding turbines are axial-flow units, and the direction of the internal flow from the guide vane domain to the runner domain undergoes a 90-degree change, which is unfavorable to the physiological activities of fish. The fish body inside the traditional water turbine is greatly affected by machinery, pressure, shear force, etc.

Contents of the invention

Aiming at tidal energy and ocean current energy power generation, the present invention develops a fish-friendly type tubular water turbine, which utilizes water level difference or ocean kinetic energy to generate electricity, aiming at improving the survival rate of passing fish under the premise of ensuring the hydraulic performance of the water turbine, and at the same time ensuring The hydraulic efficiency of the water turbine is better, and the fish passing ability of the water turbine is improved, so as to help the green development of hydropower projects and ecological projects.

The present invention adopts following technical scheme to realize:

A kind of fish-loving type tubular water turbine, the flow area of the water turbine includes a water inlet chamber, a guide vane area, a runner with helical blades, a discharge cone connected to the main shaft, a diffusion section and an extension section of the outlet pipe, which are connected in sequence, wherein , the cross section of the water inlet chamber is square, the guide vane profile line located in the guide vane region is a positive curvature crescent shape, the runner blade of the runner is a helical blade, and the ratio of the initial pitch to the cut-off pitch of the helical blade is 1:5, The inner discharge cone of the wheel is a circular table type, and the ratio of the length of the diffuser section of the outlet pipe to the extension section of the outlet pipe is 1:4.

The further improvement of the present invention is that the inlet cross section of the water inlet chamber is a square with a side length of 1.95D ₁ , the flow channel of the water inlet chamber is 2.618D ₁ long and the outlet diameter is 1.46D ₁ .

The further improvement of the present invention is that a pillar is placed at a distance of 1.814D ₁ from the inlet of the water inlet chamber to support the bulb body, the diameter of the head of the bulb body is 0.892D ₁ , the maximum diameter is 1.167D ₁ , and the diameter of the tail is 0.153D ₁ ; The distance from the entrance of the water inlet chamber is 0.906D ₁ , and the wall thickness of the bulb body is 0.041D ₁ ; the upper part of the bulb body is provided with a length of 0.211D ₁ and a width of 0.067D _{1 .} Shaft access.

The further improvement of the present invention is that the guide vanes in the guide vane domain are uniformly distributed in a single row annular manner, the included angle α ₁ between the center line of the guide vanes and the central axis of the water turbine is 65°, and the throat diameter _D of the guide vanes and the runner inlet diameter D ₁ The ratio is 0.111, the number of guide vanes is 11 to 14, the guide vane is a positive curvature blade shape, and the tail end of the guide vane is naturally closed. The profile equation is:

A:

B:

The further improvement of the present invention is that the ratio of the axial length of the runner to the diameter of the runner is 1:3.659.

The further improvement of the present invention is that the runner blades are variable-pitch helical blades, the ratio of the initial pitch to the cut-off pitch of the helical blades is 1:5, the blades are equal in diameter in the radial direction, and the blades are equal in thickness, and the bone line of the runner blades Equation C is:

The further improvement of the present invention lies in that the taper of the water discharge cone is 0.5-0.6.

The further improvement of the present invention lies in that the diffusion angle of the diffusion section of the outlet pipe is _α2 which is 10°-13°, and the ratio of the length of the diffusion section of the outlet pipe to the extension section of the outlet pipe is 1:4.

Compared with the prior art, the present invention has significant advantages in that:

First, the fish-friendly tubular turbine proposed by the present invention is a tubular structure, and the entire flow channel is similar to the auxiliary fishway of the power station. Compared with the axial flow unit, there is no flow direction of 90 degrees from the guide vane to the runner. The additional damage to fish caused by turning is better than that of axial flow turbines.

Second, the inner blade of the runner of a fish-friendly type tubular water turbine proposed by the present invention is a helical blade, and the helical flow channel is opposite to the slit cross-section flow channel, and the space for passing fish is better, which effectively reduces the mechanical damage to fish and shear damage, significantly improving the survival rate of fish.

Thirdly, the fish-friendly type tubular water turbine proposed by the present invention can be used for the utilization of tidal energy of building reservoirs and the utilization of ocean current energy. While improving efficiency, it has specifically achieved the friendly and coordinated development of energy development and utilization and ecological and environmental protection construction.

Description of drawings

Fig. 1 is a structural schematic diagram of a fish-loving type tubular water turbine proposed by the present invention.

Figure 2 is a schematic diagram of the guide vane structure.

Fig. 3 is a schematic diagram of the profile of the guide vane in Fig. 2 .

Figure 4 is a schematic diagram of the structure of the runner.

Fig. 5 is a schematic diagram of the runner blade in Fig. 4 .

Fig. 6 is a schematic diagram of the structure of the water outlet pipeline.

Figure 7 is a structural diagram of the draft tube.

Explanation of reference signs:

1-Water inlet chamber, 2-Bulb body, 3-Support, 4-Bulb body shaft channel, 5-Guide vane area, 6-Guide vane, 7-Runner, 8-Runner blade, 9-Drain cone, 10-the diffuser section of the outlet pipe, and 11-the extension section of the outlet pipe.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figures 1-7, the ichthyophile type tubular water turbine provided by the present invention specifically includes a water inlet chamber 1, a bulb body 2, a support 3, a bulb body shaft channel 4, a guide vane area 5, a runner 7, Water discharge cone 9, outlet pipe diffusion section 10 and outlet pipe extension section 11. Wherein the cross section of the inlet of the water inlet chamber is a square, and a pillar is placed at 78% of the distance between the inlet chamber and the inlet of the water inlet chamber. The bulb body 2 is provided with a shaft passage 4 for entering and leaving the bulb body. The guide vanes 6 are distributed in a single-row annular manner, the angle α ₁ between the center line of the guide vanes 6 and the central axis of the turbine is 65°, the ratio of the throat diameter D _T of the guide vanes to the diameter D ₁ of the runner inlet is 0.111, and the number of guide vanes is 12 , the guide vane is a positive curvature blade. The 8 surfaces of the runner blades are three-dimensional variable-pitch helical surfaces, and the blades are equal in diameter and thickness in the radial direction. The diffusion angle of the diffusion section 10 of the outlet pipe is 11°, and the ratio of the length of the diffusion section 10 to the extension section 11 is 1:4.

When the turbine is running, the water flow flows into the water inlet chamber 1, bypasses the bulb body 2, the support 3, forms a certain circulation through the guide vane 6, and then enters the runner 7, pushing the runner blade 8 to rotate, and the water flow after doing work is diffused through the outlet pipe Section 10, water outlet pipe extension section 11 flows out. As shown in Figure 3, the guide vane profile equation is:

A:

B:

As shown in Figure 5, the blade bone line equation is:

After hydraulic calculation, according to the calculation results, it can be seen that the variable pitch helical blade of the present invention not only ensures the operation efficiency of the water turbine, but also effectively reduces the mechanical damage and shear damage to fish due to the better fish passing space, and significantly improves the Fish survival rates. The fish-breeding type tubular turbine performed well in two types of simulation studies of tidal energy utilization in reservoir construction and ocean current energy utilization in seabed placement, which is conducive to the coordinated development of hydropower projects and ecosystems.

The realization principle of the present invention is: a fish-friendly type tubular water turbine proposed by the present invention is a device for converting the energy of water flow into mechanical energy. The fish-breeding turbine can not only generate power by using the tidal energy of building a reservoir, but also use ocean current energy to do work. Its inlet chamber adopts a gradual transition from a rectangular section to a circular section. This structure is convenient for installing the unit when using ocean current energy. The water guide mechanism adopts uniformly distributed positive curvature blade shape, and the outlet flow of the guide vane enters the runner along the outer edge of the runner. The runner blades are variable-pitch helical blades, and the better flow space effectively reduces the mechanical damage and shear damage to fish, and significantly improves the survival rate of fish passing through the machine. The pressure of the water flow and the fish from the inlet to the outlet of the runner gradually decreases, and finally flows out through the outlet pipe.

The description not involved in the specific implementation of the present invention belongs to the known technology in this field, and can be implemented with reference to the known technology. The above specific implementation methods and examples are specific support for the technical idea of a Francis long-short blade water turbine proposed by the present invention, and cannot be used to limit the protection scope of the present invention. Any equivalent changes or equivalent changes made on the basis all belong to the protection scope of the technical solution of the present invention.

Claims (6)

1. A fish-friendly type tubular water turbine, characterized in that, the flow area of the water turbine comprises a water inlet chamber (1), guide vane domain (5), and a runner (7) with helical blades (8) connected in sequence , the discharge cone (9) connected to the main shaft, the diffuser section (10) and the extension section (11) of the outlet pipe, wherein the cross section of the water inlet chamber (1) is square, and the guide vane (6) located in the guide vane domain (5) ) profile is a positive curvature crescent shape, the runner blade of the runner is a helical blade (8), and the ratio of the initial pitch of the helical blade (8) to the cut-off pitch is 1:5, and the internal discharge of the runner (7) The cone (9) is a circular table type, and the ratio of the length of the outlet pipe diffusion section (10) to the outlet pipe extension section (11) is 1:4; The guide vanes (6) in the guide vane domain are evenly distributed in a single-row annular manner, the angle _α1 between the centerline of the guide vanes (6) and the central axis of the turbine is 65°, and the diameter D _T of the throat of the guide vanes (6) is the same as that of the runner (7 ) The inlet diameter D ₁ ratio is 0.111, the number of guide vanes (6) is 11 to 14, the guide vanes (6) are positive curvature blades, and the tail ends of the guide vanes (6) are naturally closed, and the profile equation is: A:

B:

2. A fish-friendly type tubular water turbine according to claim 1, characterized in that, the inlet section of the water inlet chamber (1) is a square with a side length of 1.95D ₁ , and the flow channel of the water inlet chamber (1) is long 2.618D ₁ And the outlet diameter is 1.46D ₁ . 3. A kind of fish-friendly type tubular water turbine according to claim 1, characterized in that, a pillar is placed at _1.814D from the inlet of the water inlet chamber (1) to support the bulb body (2), and the head of the bulb body (2) The diameter is 0.892D ₁ , the maximum diameter is 1.167D ₁ , and the tail diameter is 0.153D ₁ ; the distance between the head of the bulb body (2) and the inlet of the water inlet chamber (1) is 0.906D ₁ , and the wall thickness of the bulb body (2) is 0.041 D ₁ ; at the upper part of the bulb body (2) at a distance of 1.674D ₁ from the inlet of the water inlet chamber (1), there is a shaft passage (4) for entering and exiting the bulb body (2) with a length of 0.211D ₁ and a width of 0.067D ₁ . 4. A fish-loving type tubular water turbine according to claim 1, characterized in that the ratio of the axial length of the runner (7) to the diameter of the runner is 1:3.659. 5. The fish-breeding type tubular water turbine according to claim 1, characterized in that the taper of the discharge cone (9) is 0.5-0.6. 6. a kind of fish-friendly type tubular water turbine according to claim 1, is characterized in that, the diffusion angle of the outlet pipeline diffusion section is α ₂ is 10 ° ~ 13 °, the outlet pipeline diffusion section (10) and the outlet pipeline extension section (11) The length ratio is 1:4.

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