Study on the Digital Simulation of Hydraulic Characteristic for Complex Bifurcated Channel during Flood

2D mathematical model of an engineering example is utilized to simulate a complex bifurcated channel. Considering three conditions (natural, case 1 and case2), we calculated the hydraulic coefficients of split ratio, water level and velocity, and analyzed the influences brought out by these two cases. The results show that the auxiliary dam could simplify the terrible flow state of the bifurcated channel upstream, but raise the water level and velocity in diversion channel. Both two cases can ensure the left and middle channel safe during flood and case 2 is better for diversion channel because 2# bifurcation can reduce the hydraulic coefficients significantly.