Water Resources and Power

In order to investigate the impact of different section forms of trash rack bars on trash rack head loss,the head loss of different trash rack and the flow characteristic are obtained based on the CFD numerical simulation technology and theκ-εturbulence model.And then the numerical results are compared with the results based on the empirical formula.It shows that the local head loss obtained from the numerical calculation is in good agreement with the empirical formula.The head loss of the trash rack with circular cross section is minimal,and the water flow transition is the most gentle.The head loss of the trash rack with square section is maximal,and the water formed a large vortex with rapid transition velocity and strong turbulence followed by the flow of the bar of trash rack.The farther the distance between the flow and the trash rack is,the smaller the influenced flow will be;the streamline tend to be parallel gradually until return to the upstream of the trash rack with the same flow regime.