摘要
By discretizing the convection terms with AUSM+-up scheme in the rotating coordinate system,a finite volume analysis code based on multi-block 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.
By discretizing the convection terms with AUSM＋-up scheme in the rotating coordinate sytem,a finite volume analysis code based on multi-block structured grids was developed indeso as to realize the numerical solving of internal flow fields of turbomachineries. Takingradial impeller with the working fluid of water vapour as the research object,the flow response to thefluctuation of rotational speed was calculated. By comparing the surface pressure profilescontours calculated by the code and commercial software respectively,the accuracy of flow solver wasverified. The analysis of flow response data indicates that,as the working condition shifts closer twards the surge boundary,the response of flow parameters such as mass flow and aerodynamic towill be more nonsynchronous with the fluctuation of rotational speed,and also the influence of densitvariation on mass flow variation will be smaller. Moreover,the transient variation region of workicondition performance will deviate farther away from the steady performance curve as the wodition approaches the surge boundary. Compared to the working conditions with small mass f,thedistribution characteristics of pressure difference load on the blade surface vary little uflow conditions. The reduction of fluctuation amplitude of rotational speed exerts no inflting the hysteresis of flow response.
出处
《排灌机械工程学报》
EI
CSCD
北大核心
2016年第8期693-702,共10页
Journal of Drainage and Irrigation Machinery Engineering
基金
supported by the National Key Basic Research Program of China (No.2012CB026000 )
the National Science Foundation for Young Scientists (No.2014011155)
