建立表征离心压气机叶轮积垢分布的粗糙度模型,在叶片表面生成三维、非均匀分布的粗糙带,数值研究干净和积垢状态下叶轮的气动性能和内部流场,并通过敏感性分析,找到对叶轮气动性能影响最大的积垢区域。结果表明:积垢叶轮的多变效率和总压比较干净叶轮均有显著下降;随着流量增大,性能衰减愈发明显;离心压气机叶片前缘靠近叶顶部位为气动性能对积垢的最敏感区域.研究工作为离心压气机的鲁棒设计优化奠定了理论基础。
Based on the fouling modeling of the centrifugal impeller blade through a three-dimensional nonuniform surface roughness map,detailed CFD simulations are performed to investigate the aerodynamic performance and flow fields of both clean and fouled impellers.The sensitivity analysis is conducted to find out the most important contaminated region causing the performance degradation. The results show that the fouled impeller has significantly reduced polytropic efficiency and total pressure ratio than the clean impeller;as the flow rate increases,the performance degradation becomes more pronounced.With the sensitivity analysis,the most important contaminated region associated with the impeller performance degradation is located at the blade tip at the leading edge.This study can provide theoretical foundation for the robust optimization design for the centrifugal impeller.