基于流固耦合的离心泵启动过程瞬态叶片动应力特性

摘要

为研究离心泵启动过程的叶片的应力和变形情况，针对 IS65－50－160的离心泵启动过程瞬态内部流场和结构场进行了双向流固耦合联合求解。其中流场计算基于 RANS 方程与 SST 湍流模型；结构场计算基于弹性体结构动力学方程；对叶轮叶片在双向流固耦合作用下的变形和应力分布进行了计算，获得了离心泵启动过程中瞬时效应对叶片应力和应变的影响规律。研究结果表明：叶片的最大等效应力和应变呈振荡上升趋势，振动强度先减小后增大；在离心泵启动过程中，叶片进口与后盖板的交界处出现应力集中，叶片的变形量从后盖板到前盖板呈递增的趋势；叶片的最大等效应力和应变量都大于稳态工况下的最大等效应力和应变量。%In order to predict the stress and deformation during the transient state of the centrifugal pump startup period,a coupled solution of a flow field in the pump and a structural response of the blades was established using a Fluid-Structure Interaction method.The flow field prediction was based on the Reynolds-averaged N-S equations and the SST turbulence model,while the structure prediction was based on elastic structural dynamic equation.Based on the transient numerical simulation results,the Fluid-Structure Interaction method was used to solve the internal flow field and the structure field during the centrifugal pump startup period.The results showed that:the maximum equivalent stress and strain of the blade show a vibration that increases;the vibration intensity decreases first and then increases;an intense increase occurs in the impeller inlet near the hub;the blade deformation shows a trend that increases from the hub to the shroud;and the maximum equivalent stress and strain of the blades are greater than those in the steady-state conditions.