Numerical Study of Three-Dimensional Surface Jets Emerging from a Fishway Entrance Slot

The efficiency of a fishway is determined by the ability immigrating fish to follow its attraction flow (i.e., jet) locate and enter entrance. hydraulic characteristics entrance jets can be simplified using findings from widely investigated surface produced shaped nozzles. However, effect different boundary conditions (characterized vertical slots) compared nozzle must considered. We investigate downstream propagation slot into quiescent tailrace, considering following not considered for jets: (1) geometry, (2) turbulence approach slot, (3) presence lateral wall slot. quantify these three-dimensional hydrodynamic-numeric simulations with DES RANS models volume-of-fluid method (VoF) simulate free water surface. In addition, we compare jet existing analytical methods describing propagations show that turbulent inhomogeneous towards reduces length in tailrace due increased spreading nozzle. An additional significantly increases length. For highly flows at entrances, model tends overestimate transient model.