为了解决传统处理机匣对压气机"扩稳降效"的现象,打破处理机匣结构的轴对称传统,并设计了5种不同周向分布范围的非轴对称处理机匣.实验结果显示压气机的稳定裕度随非轴对称处理机匣的周向处理槽数的增多而单调增加,而效率则随处理槽数的增多先增加后减小.当非轴对称处理机匣的周向处理范围为120°时,能使压气机的稳定裕度和效率均有所增加,起到"扩稳增效"的效果.初步分析其原因是非轴对称的机匣结构改变了压气机叶尖的非定常流动.
In order to solve the problem that traditional casing treatment increases the stall margin while reducing the efficiency of compressor, five innovative non-axisymmetric casing treatments with different circumferential treating angles were designed in this paper. In a series of experiments, the stall margin of a compressor increased with the rise of circumferential treating angle, while the isentropic efficiency rose up firstly and fell down later. It was interesting that the stall margin and efficiency of the compressor were both enhanced when the circumferential treating angle of the non-axisymmetric casing treatment was 120°, the reason of which was simply attributable to the fact that non-axisymmetric configuration changed the unsteady tip flow in the compressor.