FIELD: hydraulic engineering. SUBSTANCE: proposed method comes to creating controlled water flow depending on difference in levels of upper and lower pools and type of fish. Rectangular fishway (swim-in) hole is made in upper wall separating upper pool lower one and jet forming nozzles are installed over perimeter of hole at angle to hole axis. Water flowing through these nozzles forms two rows of parallel drowned hydraulic napes pointed towards upper pool from fishway hole with initial velocity V0. Relative interaction of napes takes place at a certain distance X1 from fishway hole, thus forming summary flow. At further propagation of summary flow, axial velocity is reduced due to pulsation velocities (flow area F is increased) and counterflow velocity which depends on difference in water levels in upper and lower pools. At a certain distance X2 axial velocity Vx of summary flow propagation tends to 0, and flow in this direction fades. Thus, zone of partial equal pressures is formed: pressure (hydraulic stop) of summary flow at a distance X2 from vertical wall, and pressure built by water column (head) H from side of upper pool. Barrier wall can be used to decrease ejection of summary flow. By changing initial conditions of nappe flowage velocity V of controlled water flow attracting the fish can be changed to suit type of moving fish. Zone of partially equal pressures provides unobstructed passage of fish from lower pool of hydraulic works into upper pool and back. EFFECT: provision of safe passage of fish. 1 dwg
