SU1765284A1 - Fishway - Google Patents

Abstract

The invention relates to hydraulic engineering and is intended to collect the rolling fish from the surface layer of the upstream and the subsequent descent of the fish into the downstream. The purpose of the invention is to increase the working efficiency. The rolling fish fry, located in the surface layer of the upper pool 1 formed by the dam 2, moves in the stream above the ramp 6 to the water intake holes 5 made in the side wall of the tray 3. Through the water inlets 5 the sloping young fish enters the tray 3 connected fish diverter 4, through which it is diverted to the downstream. The implementation of an inclined ramp 6 adjacent to the bottom of the water intakes 5 with the possibility of changing its length and angle of inclination to the horizon allows the depth of the surface water layer to be removed. 2 Il.

Description

The invention relates to hydraulic engineering and is intended to collect the rolling fish from the surface layer of the upstream and the subsequent descent of the fish into the downstream.

The aim of the invention is to increase efficiency.

FIG. 1 shows a device for lowering rolling fish, top view; in fig. 2 shows section A-A in FIG. one,

The device has a trough-shaped tray 3 located in the upstream 1 formed by the dam 2 and connected to a fish diverter 4. In the side wall of the tray 3, surface water intake holes 5 are made, the bottom of which is attached to its bottom by an inclined ramp 6, made in the form of a waterproof plate, while the lower edge of the ramp 6 is made rounded and recessed sublevel water surface

upstream 1 to the depth of the hH fish. In order to make it possible to use a device for collecting fish living in the surface water layer of the upstream 1 of various depths, the ramp 6 is made with the possibility of changing its length and angle to the horizon. Tray 3 is installed with the possibility of vertical movement, for example, floating or moving along rails fixed in the body of the dam 2.

The angle of inclination of the ramp 6 to the horizon is determined by the dependence

and arcs in -7 (1 -k)

In

where hH - the depth of the lower edge of the ramp;

n is the length of the ramp;

VI (

cl

Yu

00

TO

Up vc

- coefficient numerically equal to the ratio of the threshold vn and the drift vc flow rates for fish,

In order to reduce injury to the fish when moving over the ramp 6, the lower edge of the ramp is rounded.

The device for the descent of the rolling fish works as follows.

Located in the surface layer of the upstream 1, formed by the dam 2, the young fish fry searches for passage ways through the dam 2 and accumulates in front of its pressure front. The fish flow rates ahead of the pressure front of dam 2 are drastically reduced. Under these conditions, the fish are disoriented and their orientation in the stream can be restored and the search for culvert openings in dam 2 can be intensified by organizing the flow in the fish-saturated surface layer with velocities not less than threshold vn. Therefore, being found during searches above the lower edge of ramp 6, at flow rates not less than the threshold speed for fish vn, i, the sloping fish restore orientation in the stream and, following the slope instinct, move in the direction of the water intake holes 5 Deepening the bottom the edges of the ramp 6 under the level of the free surface by an amount not less than the depth of the sloping fish ensures that they get into the space above the ramp 6

Moving in the stream above the ramp 6 in the direction to the culvert holes 5, the gently rolling fish experience an increase in the speed of their transporting stream, which increases to a value not less than the drift velocity for fish vc above the upper edge of the ramp b located at the bottom of the water intake ports 5 Fish moving over ramp 6, through the water intake holes 5 get inside the tray 3, the fish-carrying stream from which enters the fish drain 4, and from it - to the lower reach of the dam 2.

Part of the fish that turned out to be near the edges of the holes 5, under the effect of a startle response or because of unwillingness to get into the water intake holes 5, will make a sharp movement against the flow (throw) at speeds exceeding the drift, called throw vs. vs. The time during which the fish can move at shooting speeds is a fraction of a second. In order for the fish during the throw not to go beyond the ramp 6 with an organized fish-orienting stream, it is necessary that the length of the ramp 6 be sufficient.

It is known that the maximum path a fish can take at a throwing speed does not exceed 30-50 lengths of its body, and the minimum path is 5-10 lengths of its body. Thus, with the length of the ramp 6, which is 10-50 body lengths of the gentle fish, they will not be able to go beyond the ramp 6 in the throw. Then, under the action of the orienting flow and the gentle instinct, the fish will again start moving to the water intake holes 5 and so on. until they fall into tray 3 through them.

The implementation of the tray 3 with the possibility of vertical movement allows to accurately monitor and isolate the fish-saturated surface layer of the upstream 1 and to prevent the flow of water through the device during the period when there are no gentle migrations of fish.

The implementation of the ramp 6 with the possibility of changing its length allows for a stable hydraulic flow structure above the ramp 6 when the depth of the fish-saturated surface layer changes.

Claims (1)

Invention Formula A device for lowering rolling fish through a dam comprising a tray with surface water intake holes in the side wall and a fish guide element adjacent to the bottom of the holes, characterized in that the fish guide element is designed as a ramp installed with the possibility of changing its length and angle of inclination to the horizon, with the upper edge of the ramp adjacent to the bottom of the holes, and the lower edge is rounded, while the tray is installed with the possibility of vertical moved . 2 J five 1