Parametric study on active flow control of a transonic axial compressor rotor using endwall synthetic jet

Abstract

High-load axial compressor is the mainstream of current compressor design and development. In order to improve the aerodynamic performance of high-load axial compressor, an active flow control method in which a synthetic jet is applied to the endwall is proposed. Taking the transonic axial compressor NASA Rotor 35 as the research object, using a single factor analysis method, the influence of five different excitation positions, three different excitation frequencies, and three different jet peak velocities on the aerodynamic performance of the compressor was studied in turn, and obtained the influence law of the endwall synthetic jet excitation parameters. The results show that all three parameters have important effects on the performance of the compressor. Among the excitation parameters studied in this paper, there is an optimal excitation position of 25% Ca. When excited at this position, the flow margin of the compressor is expanded the most. On the basis of maintaining the optimal excitation position and the maximum jet peak velocity, the calculation results found that the jet frequency has little effect on the compressor’s near stall flow rate, but has a great impact on the total pressure ratio and efficiency. The pressure ratio and efficiency increase with the increase of the excitation frequency. However, there seems to be a threshold of the excitation frequency. Only when the excitation frequency is greater than the threshold can the total pressure ratio and efficiency be higher than the prototype compressor. The jet peak velocity has the smallest impact on the compressor performance. Based on the optimal excitation position and the excitation frequency exceeding the threshold, even if the jet peak velocity is small, the compressor can obtain a higher flow margin, total pressure ratio, and efficiency than the prototype compressor. As the jet peak velocity increases, the performance of compressor can be further improved.