泵转子流固弱耦合计算与分析

Numerical simulation of pump rotor using weaker fluid-solid interaction approach

为了探索流固弱耦合计算在推进泵上应用的可行性和有效性,完成了某转子静强度、动强度和振动模态计算与分析。首先,完成泵稳态和瞬态流场CFD计算,提取水动力载荷数据;然后,采用流固弱耦合方法对结构完成稳态和瞬态计算,提取静应力和动应力以及最大变形,校核静强度和动强度;最后,完成流固耦合条件下转子模态分析,得到模态频率和特征振型。结果表明:转子叶片最大应力位于叶根处、最大位移位于叶梢截面近随边处;转子叶片应力满足材料的强度要求,变形量小于叶顶间隙值;湿模态振型与干模态基本一致,但振型幅值明显降低、模态频率降低。该流固弱耦合计算方法能够用于泵转子结构设计与振动谐响应分析,有助于提升设计质量。

In order to explore the feasibility and effectiveness of the weaker fluid-solid coupling calculation in the propulsion pump,the static strength,dynamic strength and vibration mode of a rotor were calculated and analyzed.Firstly,the steady and transient flow fields of the pump were calculated by CFD to extract the hydrodynamic load data.And then,the steady and transient flow fields were calculated by weaker fluid-solid coupling method to extract the static and dynamic stresses and the maximum deformation of the structure.Finally,the rotor modal analysis under fluid-structure coupling condition was completed,and the modal frequency and characteristic mode were obtained.The results show that the maximum stress of rotor blade is at the root and the maximum displacement is near the edge of tip section,that the stress of rotor blade meets the requirement of material strength,and the deformation is less than the tip clearance,and that the mode shape of wet mode is almost the same as that of dry mode,but the amplitude of mode shape and mode frequency decrease obviously.The fluid-solid weak coupling calculation method can be used in the structural design and vibration harmonic response analysis of pump rotor,which is helpful for related design improvement.