基于正交试验的核主泵导叶水力性能数值优化

为提高核主泵整机水力性能,实现叶轮、导叶与环形压水室的最优匹配,以AP1000核主泵为研究对象,保持叶轮与蜗壳几何参数不变,选择导叶进口冲角、导叶包角和导叶出口角为正交试验方法的3个因素,并根据各因素的值确定取值范围。基于雷诺时均N-S方程、RNGk-ε湍流模型和SIMPLEC算法,应用CFD技术对核主泵进行了正交试验和数值优化。正交试验和因素显著性分析表明:额定工况下,优化后的模型泵较原模型泵扬程提高0.55m、效率提高0.66%;小流量工况下,优化后的杨程和效率提升更加明显;导叶包角和导叶出口角对泵水力性能的影响较为显著,导叶流道扩散程度决定了导叶流道的水力损失;导叶进口冲角、导叶出口角和导叶包角之间的相互作用对泵水力性能的影响不显著,可忽略。对导叶包角的研究表明,在小流量工况下,导叶包角与泵的效率呈正比,在大流量工况下,导叶包角与泵的效率呈反比。

Numerical Optimization on Guide Vane Hydraulic Performance of Nuclear Main Pump Based on Orthogonal Test

In order to improve the hydraulic performance of nuclear main pump and accomplish the best matching between impeller, guide vane and circular delivery chamber, the AP1000 nuclear main pump was chosen as the study object. The geometry parameters of impeller and volute were kept unchanged, and the attack angle of diffuser inlet, the angle of diffuser and the outlet angle of diffuser as the three factors of the orthogonal test method were chosen, and the value range was ensured according to the value of each factor respectively. Based on Reynolds time-average N-S equation, RNG k-ε turbulence model and the SIMPLEC algorithm, the orthogonal experiment and numerical optimization were completed by CFD technology. Through orthogonal test and significance analysis of factors, it is shown that under the rated conditions, the optimized model pump will improve the pump driving head 0.55 m, with efficiency increasing 0.66%, compared to the original model pump. Under small flow condition, the driving head and efficiency are more significantly optimized. The angle of diffuser and the outlet angle of diffuser have obvious effects to hydraulic performance of the pump and the flow diffusion in diffuser determines hydraulic loss of the diffuser. The interactions among the inlet angle of diffuser, the outlet angle and the angle of diffuser have little effect to the hydraulic performance of pump, which can be ignored. The research on the angle of diffuser shows that under small flow condition, the angle of diffuser is proportional to the efficiency of the pump, however under large flow condition, which is inversely proportional to the efficiency of the pump.