A fish-breeding axial-flow paddle turbine

Abstract

The invention relates to a parent-fish-type movable propeller turbine which comprises a runner chamber, a runner hub arranged in the runner chamber, blades connected with the periphery of the implemental runner hub and a guide vane connected with the top of the implemental runner chamber, wherein the runner hub comprises an upper cylindrical section, a spherical section, a lower cylindrical section and two frustum sections which are successively arranged; and the inner wall of the runner chamber successively comprises an cylindrical section, a middle spherical section and a lower throat section. The turbine is characterized in that the spherical section of the runner hub is composed of a plurality of projecting eccentric spherical crowns, and the quantity of the eccentric spherical crownsare same as that of the blades; each blade is respectively fixedly connected to the corresponding eccentric spherical crown on the runner hub, and the diameter of the cylindrical section of the runner chamber is lower than 0.98 times that of the spherical section; and the diameter of the throat section of the runner chamber is lower than 0.96 times that of the spherical section, the excircle arc semidiameter of the throat section is 0.02D1-0.1D1, the D1 represents the diameter of the runner chamber, and the spherical section of the runner chamber is a global section. The turbine provided by the invention can be widely used in hydroelectric installations.

Description

technical field [0001] The invention relates to a hydroelectric power generation device, in particular to a fish-loving type axial flow paddle water turbine. Background technique [0002] Hydropower installations usually cut off the upstream and downstream channels of fish, which has a great impact on migratory fish that rely on upward migration to complete their life cycle, and also has an impact on non-migratory fish. Fish will suffer serious injuries as they descend through ordinary water turbines. Studies by some foreign research institutions have shown that the casualty rate of fish passing through ordinary water turbines is about 30%; different designs of water turbines cause the casualty rate of fish passing through the machine to be in the range of 5% to 30%. Some foreign green environmental protection organizations and fishermen have opposed dam construction since 1980 and demanded the demolition of some hydropower stations. In recent years, the awareness of envir...

AI Technical Summary

Problems solved by technology

[0005] 2) Although the spherical section 32 is used in the middle of the runner chamber 3, since the outer arc radius of the throat section 33 at the lower part of the runner chamber is relatively large, a gap smaller than the water inlet will still be formed behind the tangent point of the two arcs. The side, the flat and long lower "wedge-shaped" gap B, this gap B does not have the characteristics of "clamping tighter" in the upper gap A, but due to the effect of centrifugal force, the probability of fish passing the machine to concentrate in this area is high, and the same Injuries can also be caused by crowding and the fish's own "struggle"

[0006] 3) There will also be a "wedge-shaped" gap C between the lower end surface of the outlet edge of the guide vane 4 and the arc of the runner chamber 3 (such as figure 1 , Figure 4 As shown), it will not only directly harm the fish, but may cause additional damage to the fish due to the vortex behind the "wedge" gap

[0008] 5) If in order to eliminate the damage of the wedge-shaped gap A, B, C, E, F to the passing machine fish, only simply shorten the blade 2 of the conventional technology (such as Figure 7 As shown by the dotted line in the middle), it will inevitably make the blade 2 a lot shorter, and even more than 1 / 3 of the blades need to be cut off from the outer edge of the water inlet edge of the blade 2, the density of the cascade will be greatly reduced, the efficiency will be reduced, and the pressure of the water outlet edge of the blade 2 will be reduced. There are more, and even cavitation will occur, and a "blade vortex" will be generated between the two blades, forming a very large shear stress, which will cause problems such as low efficiency, serious cavitation, and poor stability. , large shearing force, etc., endangering the life of the passing fish

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