A film-pulled fishway

Abstract

A film-pulling fishway relates to fishways, in particular to improvements of stepped fishways. The minimum height of the partition protruding from the bottom surface of the fishway is 1-1.5 meters; a continuous film is passed over the partition, that is, the entire fishway from the upstream fishway entrance to the downstream fishway exit is covered by a film, the two sides of the film are fixed to the upper end surfaces of the two sides of the fishway, the middle part of the film can sink to the bottom surface of the fishway, and the film is fixed at both ends of the partition when it passes over the partition; the partition can move up and down along the chute; the partition moves in the chute, the chute can accommodate the partition sliding down, the depth of the chute is the height of the partition minus the minimum height of the partition protruding from the bottom surface of the fishway, the height of the partition can make the film between the two partitions in a taut state when the partition rises to the top, so that the film presents a slope to pour water and fish into the water body surrounded by the upper partition and the fishway. It provides great help for the migration of small fish. It can save energy.

Description

Technical Field

[0001] The present invention relates to fishways, in particular to improvements of stepped fishways. Background Art

[0002] The existing fishways attached to dams, due to the existence of drop, generally adopt obstacles to dissipate energy, or adopt stepped fishways. Regardless of the method adopted, the water flow in the fishway has a minimum flow rate, which is generally designed for most fish. However, there must be weak individuals and species of fish, and for weak fish, the existing fishways have greater resistance.

[0003] In order to take care of smaller fish, the only option is to lower the slope of the fishway. The slope of some fishways has been designed to be 0.0088 (that is, the angle between the bottom of the fishway and the horizontal plane is 0.5 degrees). This will inevitably increase the length of the fishway or the curvature of the fishway (similar to the design of a winding mountain road), which is more difficult for high-drop dams with narrow banks. Summary of the invention

[0004] In order to take into account relatively weak migratory fish species, the present invention improves the stepped fishway.

[0005] The technical solution adopted by the present invention to achieve the purpose of the invention is: a film-drawn fishway, the cross-section of the fishway in the vertical direction is a rectangle, the inner height of the rectangle is 5 meters, the inner width of the rectangle is 3-10 meters, and the width direction of the rectangle is horizontal; the thickness of the fishway wall is 0.3 meters, and the slope of the bottom of the fishway is 0.015-0.035, that is, the angle between the bottom and the horizontal plane is 1-2 degrees; there is a rectangular partition every 4-5 meters in the fishway, and the thickness of the partition is 0.2 meters, which is characterized in that: the partition protrudes from the bottom of the fishway The minimum height is 1-1.5 meters; a continuous film is crossed over the partition, that is, the entire fishway from the upstream fishway entrance to the downstream fishway exit is covered by a film, the two sides of the film are fixed to the upper end surfaces on both sides of the fishway, and the middle part of the film can sink to the bottom surface of the fishway. When the film passes over the partition, the film is fixed at both ends of the partition; the partition can be lifted and lowered along the slide (the contact between the partition and the slide through the ball bearings to reduce friction is already achieved in the prior art, and the present invention can also adopt this technology; lifting and lowering movement is a common mechanical movement, which is common in life and can be achieved in various ways. Any machine that can achieve lifting and lowering can be suitable for the present invention); there is a slide on the bottom surface of the fishway below the partition, which can accommodate the partition that slides down, and the depth of the slide is the height of the partition minus the minimum height of the partition protruding from the bottom surface of the fishway. The height of the partition can make the film between the two partitions in a taut state when the partition rises to the top, so that the film presents a slope to pour water and fish into the water body surrounded by the adjacent partition and the fishway; at the same time It is recommended that the height of the partition be smaller than the height of the fishway; the thickness of the partition be slightly smaller than the width of the chute, that is, a gap is allowed between the partition and the chute for part of the downward flowing water to flow through. The purpose of the gap is to reduce the difficulty of making the partition and reduce the friction of the partition lifting and lowering. The gap facilitates the partition to be raised or lowered in the chute; the partition at the lower opening of the fishway is initially at the bottom, that is, the minimum height of the partition protruding from the bottom of the fishway is 1-1.5 meters, at which time the partition at the lower opening of the fishway is submerged 0.5-1 meter below the water surface.

[0006] The film on the inner side of the partition has a certain number of holes that allow water to seep in. The diameter of the holes is 1 cm and the interval between the centers of the holes is 3-5 cm. There are no holes in the film on the outer side of the partition within a width equal to the lowest height of the partition. The inner side of the partition refers to the side close to the upstream of the fishway, and the outer side of the partition refers to the side close to the downstream of the fishway.

[0007] The most upstream partition is fixed at the lowest height, that is, the partition closest to the upstream is not provided with a chute. The film is a soft non-elastic material, that is, the film tensile elastic coefficient is infinite. The height of the support column for fixing the film on both sides of the partition is 30-50cm, so that the film presents a chute with high sides and low middle during the fishway and lifting process.

[0008] The film is fixed on the top of the support columns on both sides of the partition. The height of each support column is equal, and the height of each support column is 30-50cm, so that the film presents a chute with high sides and low middle in the fishway and lifting process. At this time, the film between the two support columns within 0.5 meters close to the support column can be provided with holes to further reduce the amount of water poured into the inner side of the upstream partition, thereby reducing the pulling force of the film (that is, the force required to lift the partition).

[0009] The beneficial effects of the present invention are as follows: the water level difference between the inner and outer sides of the partition is 6-18 cm, that is, the vertical difference between adjacent partitions is 6-18 cm, so that larger fish can migrate in the manner of jumping in the stepped fishway; the film can promote smaller fish to enter the upstream of the water body; the holes in the film can reduce the water pouring into the upstream, thereby reducing the force required for lifting the film. The film length portion close to the partition and equal to the height of the partition is not provided with holes, which is conducive to pouring part of the water and the fish into the water body on the upstream side together, and the presence of a small amount of water can reduce the collision of the fish (when the film is just lifted, although the film has holes, the film is submerged in the water. As the film is lifted upward, the fish are pushed upstream accordingly, until the film close to the adjacent partition upstream is lifted, and since the film has no holes at this time, part of the water is lifted together with the fish into the inner water body of the adjacent partition); the film has the function of a net, which can net all the fish in the water body and pour them into the upper water body, providing great help for the migration of small fish. The amount of water flowing down the fishway can be reduced. The purpose of storing water in the dam is to generate electricity, so water is a kind of energy. Therefore, the fishway of the present invention can save energy. Since the film has the function of a net, the driving effect of lifting the film makes the height difference between the fishway partitions no longer important. Therefore, the slope of the fishway can be increased to shorten the length of the fishway. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram of a film-drawing fishway; Figure 2 This is the longitudinal section of the fishway along the A-A' direction; Figure 3 This is the longitudinal section of the fishway along the B-B' direction (longitudinal section at the partition);

[0011] Among them, 1. film, 2. fishway, 3. chute, 4. partition. DETAILED DESCRIPTION

[0012] A film-pulling fishway, the vertical longitudinal section of the fishway 2 is a rectangle, the inner height of the rectangle is 5 meters, the inner width of the rectangle is 3-10 meters, and the width direction of the rectangle is horizontal; the wall thickness of the fishway 2 is 0.3 meters, and the slope of the bottom surface of the fishway 2 is 0.015-0.035, that is, the angle between the bottom surface and the horizontal plane is 1-2 degrees (due to the upward movement of the film to promote the migration of fish, compared with the prior art, the slope can be increased, thereby shortening the fish The length of the channel); there is a rectangular partition 4 every 4-5 meters in the fishway 2, and the height difference between the partitions is 4*0.015=6cm; 5*0.035=17.5cm, that is, the height difference between the partitions is 6-17.5cm. Since the angle (slope) is small, the difference between the tangent value of the angle, the sine value of the angle and the radian value of the angle is small, and they can be indistinguishable from each other, which simplifies the estimation. The sine value is used here to estimate the tangent value (slope); the thickness of the partition 4 is 0.2 meters, and its characteristics are: the minimum height of the partition protruding from the bottom of the fishway is 1-1.5 meters (that is, the water depth outside the partition is at least 1m-17.5cm=82.5cm, and the maximum is 1.5m-6cm=144cm; there is a continuous film 1 across the top of the partition 4, parameter estimation: assuming that the minimum height of the partition is 1.5 meters, the distance between the two partitions is 5 meters, and the film in the middle part of the two partitions sinks to the bottom, then the center of the film The line connecting the two partitions forms an isosceles triangle. The base height of the isosceles triangle is the lowest partition height of 1.5 meters. The base of the isosceles triangle is the distance between the two partitions of 5 meters. The waist length of the isosceles triangle is 2.9 meters ((1.5*1.5+5 / 2*5 / 2)^0.5), and the total length of the two waists is 5.8 meters. If the partition rises to tighten the film, the partition needs to rise 3 meters ((5.8*5.8-5*5)^0.5), that is, 1.5+3=4.5 meters (it should be noted that parameter estimation is not an accurate calculation; due to the small height difference between the two partitions, it is estimated based on the two partitions being at the same height), so the fishway height of 5 meters is appropriate, that is, the entire fishway from the upstream fishway entrance to the downstream fishway exit is covered by a film (it can also be simplified as a film between the partitions, and the two ends of the film are seamlessly fixed to the two adjacent partitions and the fishway walls adjacent to the partitions, and all the films are seamlessly connected), the two sides of the film are fixed to the upper end surfaces on both sides of the fishway, and the middle part of the film can sink to the bottom surface of the fishway, and the film is fixed at both ends of the partition when it passes over the partition; the partition 4 can be lifted and lowered along the slide 3; the slide 3 is a "concave" shaped groove located on the two side walls and bottom of the fishway, the middle part of the concave shape is the fishway, and the downward extending part of the concave shape extends downward through the bottom surface of the fishway. The chute 3 can accommodate the descending partition 4. The depth of the chute 3 is the height of the partition minus the minimum height of the partition protruding from the bottom of the fishway. The height of the partition can make the film between the two partitions in a taut state when the partition rises to the top, so that the film presents a slope to pour water and fish into the water body surrounded by the upper partition and the fishway; the thickness of the partition 4 is slightly smaller than the width of the chute 3, that is, a gap is allowed between the partition and the chute, and the gap is for part of the downward flowing water to flow through. The purpose of the gap is to reduce the difficulty of making the partition and reduce the friction of the partition lifting and lowering. The gap facilitates the partition 4 to rise or fall in the chute 3; the partition at the lower opening of the fishway is initially at the bottom, that is, the minimum height of the partition protruding from the bottom of the fishway is 1-1.5 meters. At this time, the partition at the lower opening of the fishway is submerged 0.5-1 meters below the water surface. .

[0013] The film 1 on the inner side of the partition has a certain number of holes that can seep water. The diameter of the hole is 1cm, and the interval between the centers of the holes is 3-5cm. There are no holes in the film 1 on the outer side of the partition within a width equal to the minimum height of the partition. The inner side of the partition refers to the upstream side of the fishway, and the outer side of the partition refers to the downstream side of the fishway. The side of the film is connected to the top of the side wall of the fishway 2 to prevent fish from leaking out of the fishway or leaking out of the film. If the minimum height of the partition is 1.5 meters, the width of the non-porous part of the film is 1.5 meters, and the length of the fishway is 3 meters, the maximum volume of the water body held before the non-porous part emerges from the water is estimated based on the film being lifted to form a triangle. The maximum area is estimated based on an isosceles triangle, 1.5 meters is divided into two waist lengths, that is, the waist length is 0.75m, the bottom height is set to h, and the length of the bottom is x, then (0.5x) 2 +h 2 =0.75*0.75, the maximum area is 0.5x*h is 0.28m 2 , that is 0.28*3=0.84m 3The water can be pushed to the upstream water body together with the fish (in the process of membrane lifting, water will gradually enter the upstream water body, which can reduce the force required for lifting by reducing the speed of membrane lifting; at the same time, due to the continuous inflow of water upstream, the amount of water transferred upstream is very small; the part of the membrane submerged under the outer water surface will be affected by buoyancy, and only the water part held by the membrane and higher than the outer water surface will be the pulling force that needs to be borne for lifting).

[0014] The inner side of the first partition 4 is already connected to the upstream water body, and the partition 4 can be fixed at the lowest height, that is, the partition closest to the upstream is not provided with the chute 3.

[0015] The film is a soft, inelastic material, that is, the film's tensile elastic coefficient is infinite.

[0016] The partition 4 can make a circular motion along the chute 3. The cycle is performed once every certain period of time, such as one hour. Assume that there are n partitions in total, and the partition at the most upstream is the first partition. Assume that n partitions divide the fishway 2 into n water bodies. In the initial state, all the partitions are 1 / 2-1 / 4 of the height of the fishway 2, such as 1.5 meters. The last partition, i.e., the nth partition, starts to rise, and the nth partition is located at the lower opening of the fishway ( Figure 1 Not shown, the nth baffle is initially at the bottom, for example, 1.5 meters, at which point the nth baffle is submerged 0.5-1 meters below the water surface). The nth baffle rises to a position that allows the fish and water to slide to an upstream adjacent water body at a lower speed. When the fish enters an upstream adjacent water body, the last baffle, i.e., the nth baffle, drops to the lowest height of the fishway 2. Then the second-to-last baffle rises to pour the fish and water into an upstream adjacent water body. This cycle repeats until the second baffle completes the action and a cycle ends. The control method of the cycle can be program control; or the tension generated by the lifting of the baffle to the top can be used as a control signal (at the same time, the film is stretched straight to squeeze the upper surface of the baffle, which can also be used as a signal for controlling the switch); all of this can be accomplished with existing technologies.

[0017] The material of the partition is cement board, and in order to reduce weight, it can also be changed to plastic sheet or aluminum alloy sheet.

[0018] The membranes on both sides move upwards due to the stretching of the partitions. However, the membranes on the outside of the partitions do not carry the gravity of the residual water due to the holes. Since all the fish are caught in one net, the fish will not be pushed back to the downstream. The stretching of the membrane on the downstream side can also be reduced by tilting the partitions upwards toward the downstream side.

Claims

1. A film-drawing fishway, wherein the cross-section of the fishway (2) in the vertical direction is a rectangle, the inner height of the rectangle is 5 meters, the inner width of the rectangle is 3-10 meters, and the direction of the width of the rectangle is horizontal; the wall thickness of the fishway (2) is 0.3 meters, the slope of the bottom surface of the fishway (2) is 0.015-0.035, that is, the angle between the bottom surface and the horizontal plane is 1-2 degrees; there is a rectangular partition (4) every 4-5 meters in the fishway (2), and the thickness of the partition (4) is 0.2 meters, wherein: The minimum height of the partition protruding from the bottom surface of the fishway is 1-1.5 meters; a continuous film (1) is passed over the top of the partition (4), that is, the entire fishway from the upstream fishway entrance to the downstream fishway exit is covered by a film, both sides of the film are fixed to the upper end surfaces of both sides of the fishway, and the middle part of the film can be sunk to the bottom surface of the fishway, the middle part of the film refers to the film between the two partitions, and the film is fixed at both ends of the partition when it passes over the partition; the partition (4) can be raised and lowered along the chute (3), and the bottom surface of the fishway (2) below the partition and the side walls of the fishway on both sides of the partition have an integrated chute. (3), that is, the chute is composed of depressions on the two side walls and a depression on the bottom surface. The chute (3) can accommodate the partition (4) that slides down. The chute (3) plays a guiding role in the movement of the partition. The vertical depth of the chute (3) is the height of the partition minus the minimum height of the partition protruding from the bottom surface of the fishway. The height of the partition can make the film between the two partitions in a taut state when the partition rises to the top, so that the film presents a slope to pour water and fish into the water body surrounded by the upper partition and the fishway; the thickness of the partition (4) is slightly smaller than the width of the chute (3), that is, a gap is allowed between the partition and the chute. The gap is used for part of the downward flowing water to flow through. The purpose of the gap is to reduce the difficulty of manufacturing the partition and reduce the friction of the partition when it is raised or lowered. The gap facilitates the partition (4) to be raised or lowered in the chute (3); the partition at the lower opening of the fishway is initially at the bottom, that is, the minimum height of the partition protruding from the bottom of the fishway is 1-1.5 meters. At this time, the partition at the lower opening of the fishway is submerged 0.5-1 meters below the water surface; the film (1) on the inner side of the partition has a certain number of holes that can penetrate water, the diameter of the hole is 1 cm, and the interval between the centers of the holes is 3-5 cm; the outer side of the partition and the partition The film (1) within the width equal to the lowest height of the plate has no holes; the inner side of the partition refers to the upstream side of the fishway, and the outer side of the partition refers to the downstream side of the fishway; the first partition (4) is fixed at the lowest height, that is, the partition closest to the upstream is not provided with a slide groove (3); the film (1) is a soft non-elastic material, that is, the film tensile elastic coefficient is infinite; the film (1) is fixed on the top of the support column on both sides of the partition (4), and the height of each support column is equal, and the height of each support column is 30-50cm, so that the film presents a slide groove (3) with high sides and low middle during the fishway and lifting process.

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