非对称压水室对CAP1400主泵性能影响的分析研究

压水室作为主泵的边界，不仅承担着压力而且还是周向流出的导叶与单向流动的管路之间的唯一桥梁。为探究压水室对整机性能的影响，以CAP1400的1:2.5缩比模型为目标，提出了一种关于主泵非对称压水室的设计方法，并设计出4种不同几何尺寸的非对称模型。借助计算流体动力学（CFD）数值方法，得到含有口环间隙的核主泵全三维模型的内部流场、外特性及瞬态载荷信息。通过对比分析获得结论:4种非对称压水室模型将上盖板处径向载荷减小60%以上，使叶轮及总径向载荷的主频幅值减小13%以上；在保证径向载荷有明显改善的同时，还能有效提升泵体效率和扬程，前者改善更为明显，提升范围为0.57%~0.83%。 

Analysis and Research on the Influence of Asymmetric Pumping Chamber on the Performance of CAP1400 Nuclear Coolant Pump

As the boundary of the nuclear coolant pump, the pumping chamber not only bears the pressure, but also is the only bridge between the guide vane flowing in the circumferential direction and the unidirectional flow pipeline. In order to explore the influence of pumping chamber on the performance of the whole machine, a design method for asymmetric pumping chamber of nuclear coolant pump is proposed based on CAP1400’s 1:2.5 scale model, and four kinds of asymmetric models with different geometric dimensions are designed. With the computational fluid dynamics (CFD) numerical method, the internal flow field, external characteristics and transient load information of the full three-dimensional model of the nuclear coolant pump with orifice ring clearance are obtained. Through comparative analysis, the following conclusions are obtained: four asymmetric pumping chamber models reduce the radial load at the upper cover plate by more than 60%, and reduce the main frequency amplitude of the impeller and the total radial load by more than 13%; While ensuring the obvious improvement of radial load, it can also effectively improve the pump efficiency and head. The former is more obvious, with a lifting range of 0.57% to 0.83%.