Mitigation of the amplitude and celerity of dam break shock wave using combination of groyne and vertical pier

This paper aims to numerically investigate the impact of the combination of groynes and vertical piers on mitigating the amplitude and celerity of dam break wave-front. First, a robust numerical model based on the Finite Volume Method(FVM) with the Harten, Lax and van Leer(HLL) approximate Reimann's solver's technique is developed and validated with other research studies. Then many different scenarios including group of piers, group of groynes with different shapes and combination of groynes and piers are considered for dam break flow modeling. The final results showed that group of piers alone or group of groynes alone have no significant effects on the wave-front depth and celerity but, combination of L-head groyne with piers can decrease the amplitude and celerity of the dam break wavefront or flood wave. In this case, a blockage zone between the groynes and intensive backwater effects behind them were observed.