侧向引水及进水泵站进水流态CFD 模拟分析与优化

应用realizable k - e紊流模型与SIMPLEC算法，对某侧向引水及进水泵站进水侧水流流场进行数值模拟和流动分析，分析表明，该泵站的进水侧水流具有弯道水流特点，数值模拟结果与理论分析结论相吻合。根据该类泵站进水侧水流流场特点，提出采用导流栅作为水力优化途径，并以泵站进水断面处动量分布和进水池断面平均流速均匀度为评判依据，对不同的导流栅整流方案的水力优化效果进行数值模拟研究。成果表明，设置导流栅对泵站引水段的动量分布具有明显的调整作用，泵站进水断面的流速分布与引水段动量分配均匀度有关。适宜尺寸的导流栅可以有效减弱引水段的进水环流作用，使水流在转向后纵向流速较快地恢复正常分布，从而进一步提高泵站进水池流量分配的均匀度。

CFD simulation and optimization on inflow pattern of diversion and intake pumping stations with side-inlets

The numerical simulation and flow analysis on the inflow patterns of the diversion and intake pumping stations with side-inlets are made herein with the realizable k-ε turbulent model and SIMPLEC algorithm.The analysis shows that the inflows of these kinds of pumping stations have the behaviors of bend-flows,for which the numerical simulation result coincides with that from the theoretical analysis.Based on the inflow pattern behaviors of these pumping stations,the diversion grid is suggested to be taken as the way for the hydraulic optimization concerned.By taking the momentum distribution of the inflow cross-section of pumping station and the uniformity of the mean velocity at the corss-section of intake-sump as the evaluation bases,the numerical simulations on the effects from the hydraulic optimizations through various schemes of flow regulation with diversion grid are studied.The result shows that the diversion grid has a significant effect on the regulation of the momentum distribution at the diversion section of pumping station,and then the velocity distribution of the inflow cross-section is related to the uniformity of the momentum distribution at the diversion section.Generally,a diversion grid with appropriate dimension can effectively lower the impact from the circulation of inflow and make the longitudinal velocity to be more quickly recovered to the normal distribution after the direction-shift of the flow,and furthermore,increase the uniformity of the flow distribution in the intake sump of pumping station as well.