中文摘要：

为研究混流式核主泵内部流动情况,提高核主泵的水力效率,对不同结构导流体的混流式核主泵水力模型的三维湍流流场进行了数值模拟,研究导流体结构对混流式核主泵模型水力性能的影响。结果表明：对于只加导流环、导叶叶片对称布置的导流体模型泵,当导流环方案为L=15 mm、θ=15°时,模型泵水力效率值最高;对于不加导流环、导叶叶片非对称布置的导流体模型泵,当γ1取24°时,模型泵水力效率值最高;对于加导流环、导叶叶片非对称布置的导流体模型泵,当导流环方案：L=15 mm、θ=15°、导叶叶片布置方案γ1=24°时,模型泵水力效率值最高。研究结果揭示了不同结构导流体对核主泵模型泵内部流场的影响规律,为高效水力模型优化设计提供参考。

英文摘要：

To study the internal flow of the mixed-flow nuclear main pump and improve its hydraulic efficiency,we applied a numerical simulation with respect to the three-dimensional turbulence field of the hydraulic model of the mixed-flow nuclear main pump,in which the diversion bodies had different structures. Our objective was to define the influence of the diversion body structure on the hydraulic efficiency of the mixed-flow nuclear main pump model. The results show that,for a model pump with a diversion body and guide vanes whose blades are symmetrically arranged,when the scheme of the guide ring is L = 15 mm,θ = 15°,the hydraulic efficiency value of the model pump is highest. For a model pump without a diversion body for which the guide vanes are not symmetrically arranged,when the angle γ1is 24°,the hydraulic efficiency value of the model pump is highest. For a model pump with a diversion body and guide vanes whose blades are not symmetrically arranged,when the scheme of guide ring is L = 15 mm,θ = 15° and the angle γ1is 24°,the hydraulic efficiency value of the model pump is highest. These results reveal the influence of different diversion body structures on the internal flow- field characteristics of the mixed-flow nuclear main pump model,and provide a useful reference for optimizing the design of a highly efficient hydraulic model.