基于正交试验的低温泵空化性能优化设计

Optimization Design of Cavitation Performance of Cryo Pump Based on Orthogonal Experiment

选择叶轮进口直径、叶片进口安放角和叶片数为影响因素,设计3因素3水平正交试验方案,运用计算流体力学软件CFX对各模型低温泵进行数值模拟计算,研究不同叶轮参数对低温液氮输送泵汽蚀特性的影响。通过极差分析法确定了改善低温泵空化性能的最佳叶轮参数组合,对优化模型和原模型数值计算结果进行了对比,探究了叶轮空化初生和发展的规律,验证了正交试验优化方案的可行性。研究结果表明,叶轮参数对低温泵空化性能影响显著,在3个因素当中叶片进口安放角的影响最大,优化后的低温泵临界汽蚀余量变小,空化区域减小,整体空化性能改善明显,为低温泵的优化设计提供了参考。

In order to study the effect of different impeller parameters on cavitation performance of liquid nitrogen cryo pump, three-level under three-factor orthogonal test schemes for impeller inlet diameter, blade inlet angle and blade number were designed. Numerical simulation software CFX was used to simulate the flow in the model pumps. The best combination of impeller parameters to improve the cavitation performance of cryo pump was found by the range analysis. The rules of the initial growth and development of cavitation in the impeller were studied by comparing the numerical results between the optimization model and the original model. The feasibility of orthogonal test scheme optimization was verified. The results show that the impeller parameters, especially the blade inlet angle, have significant influence on the cavitation performance of cryo pump. The critical cavitation allowance of cryo pump decreases, the cavitation area diminishes, and the overall cavitation performance improves obviously after optimization. The research results provide a reference for the optimization design of cryo pump.