Side discharge into a channel flow is numerically simulated using an RNG based k ε turbulence model. It is shown that the results of the recirculation zone obtained using the RNG k ε model generally agree better ...Side discharge into a channel flow is numerically simulated using an RNG based k ε turbulence model. It is shown that the results of the recirculation zone obtained using the RNG k ε model generally agree better with the experimental results compared with those by the standard k ε model. The reason for the improvement of the results obtained using the RNG k ε model over those by the standard k ε model on this flow is analyzed. The flow at small discharge ratios is thoroughly investigated and it is found that the velocity profile at the jet exit is extremely non uniform at small discharge ratios. It is also found that the degree of the non uniformity decreases as the discharge ratio increases, and is very slight for discharge ratios larger than 2.0. The effects of calculation domain, mesh size, wall functions, bed roughness and discharge ratios on the size of separation zone are also investigated in detail.展开更多
In this paper, diffusion of the contaminants skew discharged by 2 different angles 60°90°and its flow field have been studied. The N-S equations and diffusion equations are solved by SIMPLEC method, u, v and...In this paper, diffusion of the contaminants skew discharged by 2 different angles 60°90°and its flow field have been studied. The N-S equations and diffusion equations are solved by SIMPLEC method, u, v and concention difference equations are solved by LSOR, and p' solved by direct methed and GMRES(m) ahernately. Discontinuous jet are also considered. Numerical results indicate that skew aide discharge is the prior alternative in a navigable when pollution problem is of less importance.展开更多
文摘Side discharge into a channel flow is numerically simulated using an RNG based k ε turbulence model. It is shown that the results of the recirculation zone obtained using the RNG k ε model generally agree better with the experimental results compared with those by the standard k ε model. The reason for the improvement of the results obtained using the RNG k ε model over those by the standard k ε model on this flow is analyzed. The flow at small discharge ratios is thoroughly investigated and it is found that the velocity profile at the jet exit is extremely non uniform at small discharge ratios. It is also found that the degree of the non uniformity decreases as the discharge ratio increases, and is very slight for discharge ratios larger than 2.0. The effects of calculation domain, mesh size, wall functions, bed roughness and discharge ratios on the size of separation zone are also investigated in detail.
文摘In this paper, diffusion of the contaminants skew discharged by 2 different angles 60°90°and its flow field have been studied. The N-S equations and diffusion equations are solved by SIMPLEC method, u, v and concention difference equations are solved by LSOR, and p' solved by direct methed and GMRES(m) ahernately. Discontinuous jet are also considered. Numerical results indicate that skew aide discharge is the prior alternative in a navigable when pollution problem is of less importance.
