Experimental and numerical investigation of vortex formation at multiple horizontal intakes

Yıldırım, Tuğçe
Although most of the equations given in the literature for critical submergence are for symmetrical single intakes; in practice approach flow conditions are not mainly symmetrical. In this study, formation of the vortices in asymmetrical approach flow conditions was investigated for a multiple water intake structure composed of a reservoir and several pipe systems. Different scenarios were tested when some of the intake units were in operation whereas some others were not. The geometrical and hydraulic conditions of the system such as the distance between the sidewalls of the intake and the flow discharge were altered and the critical submergence required for the formation of the vortex for each test is determined. The variation of dimensionless critical submergence with related dimensionless parameters is presented and empirical equations were derived for single, double and triple intake structures. The results of the experiments were compared with each other and with those presented in the literature. This investigation has done both experimentally and numerically where software namely FLOW-3D was used in the three dimensional numerical simulations. Numerical and experimental results were compared. It was shown that it is not easy to capture air entrainment and free surface dynamics by numerically


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Citation Formats
T. Yıldırım, “Experimental and numerical investigation of vortex formation at multiple horizontal intakes,” Ph.D. - Doctoral Program, Middle East Technical University, 2020.