Three-dimensional simulation of a side discharge into a cross channel flow

Abstract A three-dimensional side discharge into a cross channel flow is simulated by a RNG based k-ϵ model. By comparison with experimental results and those from the standard k-ϵ model, it is shown that the recirculation zones calculated using the RNG k-ϵ model generally agree well with the experimental results, while the standard k-ϵ model under-estimates the length of the recirculation zone significantly. The main reason for this improvement by the RNG k-ϵ model is due to the decrease of predicted eddy viscosity. The numerical results show that the size of the recirculation zone varies slightly in the vertical direction, and the recirculation length is reduced by wall roughness. Effects of the jet to the cross channel width ratios on the size of the recirculation zone are also investigated in detail, and correlation formulas of recirculation length and width depending on velocity ratio and width ratio are proposed.