非定常机匣处理扩大压气机稳定裕度实验

从非定常角度出发,设计了一种通过改变斜槽和气室来调节壁面阻抗边界条件的非定常处理机匣,并对其开展扩大轴流风扇/压气机旋转失速稳定性的实验研究.研究工作包括:对非定常处理机匣进行流量-压比特性实验,研究其扩稳效果;对处理机匣的结构参数(斜槽、气室)进行可调节特性实验;对机匣处理的效率特性进行实验评估.结果表明:这种非定常机匣处理在三台低速风扇/压气机实验台上,通过调节机匣参数,不仅能够实现在不同的工作转速下对压气机稳定裕度有显著效果,而且效率没有明显改变.

An experimental investigation of rotating stall margin improvement with unsteady casing treatments

Casing treatments are widely used to enhance the stall margin of fans or compressors of aircraft engines.However,the existing design of casing treatment is generally on the basis of trial and error method and its application always results in efficiency loss of fans or compressors.So,how to understand the mechanism of stall margin improvement with casing treatments and how to design better casing treatments have long been an area of vigorous research activity.Based on the knowledge of the unsteady characteristics caused by casing treatment,it is verified that recessed casing treatment can be modeled as a wall boundary condition,which can be calculated by means of vortex sound theory.In the present work, a series of experimental investigations were conducted with emphasis on the effect of unsteady casing treatments on the stall margin and efficiency of three different low speed fan/compressor facilities.The results show that the unsteady casing treatments do improve the stall margin without incurring recognizable efficiency loss of the concerned fan/compressor.