摘要 By discretizing the convection terms with AUSM+up scheme in the rotating coordinate system, a finite volume analysis code based on multiblock structured grids was developed independently so as to realize the numerical solving of internal flow fields of turbomachineries. Taking an unshrouded radial impeller with the working fluid of water vapour as the research object, the flow response to the fluctuation of rotational speed was calculated. By comparing the surface pressure profiles and velocity contours calculated by the code and commercial software respectively, the accuracy of flow solver was verified. The analysis of flow response data indicates that, as the working condition shifts closer towards the surge boundary, the response of flow parameters such as mass flow and aerodynamic torque will be more nonsynchronous with the fluctuation of rotational speed, and also the influence of density variation on mass flow variation will be smaller. Moreover, the transient variation region of working condition performance will deviate farther away from the steady performance curve as the working condition approaches the surge boundary. Compared to the working conditions with small mass flows, the distribution characteristics of pressure difference load on the blade surface vary little under large mass flow conditions. The reduction of fluctuation amplitude of rotational speed exerts no influence on abating the hysteresis of flow response.
通讯作者:
XIAO Jun(1979—), male, Ph.D.(xjcompressor@163.com), researching in numerical simulation and experimental investigations of turbomachinery.
作者简介: ZHAO Yuanyang(1978—), male, Ph.D.(yuanyangzhao@163.com), researching in compressor technology.
引用本文:
XIAO Jun, ZHAO Yuanyang, SHU Yue. Analysis of flow response to fluctuation ofrotational speed in a radial impeller[J]. 排灌机械工程学报, 2016, 34(8): 693-702.
