基于CFD的高温减压塔底泵次级叶轮优化设计

运用Fluent软件,利用有限体积法对雷诺时均Navier-Stokes方程进行数值离散,采用标准k-ε湍流模型及SIMPLEC算法进行求解,对9组由不同出口宽度的次级叶轮与不同喉部面积的蜗壳所组合成的高温减压塔底泵的次级内部流场进行了数值模拟与性能预测,基于预测结果绘制了性能曲线,并分析了叶轮出口宽度与蜗壳喉部面积对性能的影响.分析结果表明：随着喉部面积的增大,蜗壳进口宽度增大,小流量区蜗壳中更易产生回流,致使扬程降低,高效区向大流量偏移;增大叶轮出口宽度,可扩大高效范围.分析结果为高温减压塔底泵次级叶轮的优化设计提供了参考,选择C-b组合为最终优选方案.

Optimal design for secondary impeller of decompression tower bottom pump with high temperature by CFD

Nine groups of secondary internal flows of the decompression tower bottom pump on high temperature were simulated by Fluent,which consisted of the secondary impellers with different outlet widths and the volutes with different throat opening areas,and their performance characteristics were predicted by using finite volume method to disperse Reynolds-Averaged Navier-Stokes（RANS） equations,stan-dard k-ε turbulence model and SIMPLEC algorithm.According to the predicted results,the perfor-mance curves were plotted and the influence caused by the outlet widths of the impellers and the throat opening areas of the volutes were analyzed.The analyzing results indicate that with the throat opening area increasing,the inlet width of volute increases,the back flow easily emerges at small flow rate,the head reduces,and high efficiency area moves to large flow,increasing the impeller outlet width can enlarge high effective area range.It provides reference for the optimal design of the pump,and the combination C-b is considered to be the best option.