Parametric Investigations on Unsteady Flow Control of Micro Axial Fan Blade Tip
Due to the reduction of micro turbofan engine size,the flow loss mainly caused by tip leakage vortex in the fan is quite serious,which affects the stable working range of the fan.A passive unsteady flow control method is adopted,namely,unsteady excitation is realized through casing opening and self-circulation air entraining to improve the fan tip flow field.The influence law of major excitation parameters such as excitation frequency and intensity on the control effect is studied by CFD numerical simulation.The results show that the optimal stability expansion effect can be obtained when the excitation frequency is the main frequency of the leakage vortex.With the effective control scheme,when the excitation flow rate is only 0.06％of the main flow rate,the compressor's comprehensive stability margin can be increased by 31％,and the peak efficiency can only lose 0.37 percent point,which explores the way for the development of high performance micro turbofan engine.
万方数据
维普
