周向总压畸变在轴流压气机中的传递特性预测新模型

A New Model for Predicting Circumferential Pressure Distortion in Multistage Axial Flow Compressor

基于轴流压气机分级级特性,建立了一种预测周向总压畸变沿轴流压气机传递的级矩阵分析新模型。应用新模型于2个轴流压气机算例,对其进口总压畸变传递特性进行了详细的数值分析,新模型预测的总压、总温及气流角的周向分布与叶排特性模型结果比较表明,新模型和采用的方法合理、可行。新模型计算结果表明,随着压气机工作点向不稳定边界移动,压气机级出口的总压畸变衰减程度明显降低,并且其级出口周向总温分布不再与转子进口绝对流动角周向分布相对应,其级进口绝对流动角减小、攻角增大,这主要与压气机级特性分布规律变化有关,显然这对压气机性能及稳定工作范围产生不利影响。

Purpose. Although there exists Ref. 2 which is theoretically very helpful to a deep understanding of circumferential pressure distortion,the amount of computation required by Ref. 2 is almost prohibitive. We are forced to get by with a new model that is not so unwieldy as that of Ref. 2. In the full paper,we explain our new model in detail; in this abstract, we just give a brief outline of our explanation. Mathematically speaking, our new model requires eqs. （1）through （9） in the full paper ; eqs. （1）through （3） are taken from Refs. 5 and 6; we derived eqs. （4） through（9）,where eq. （4）is short for eqs. （4a）, （4b）, （4c） and （4d）. Thus we establish a new model for the prediction of the decay of steady circumferential pressure distortion in multistage axial flow compressor based on stage characteristics, whose flow coefficient φ, pressure coefficient ψp, and temperature coefficient ψT are given respectively by eqs. （1）, （2） and （3） taken from Refs. 5 and 6. We develop an efficient calculation procedure for predicting stage-bystage propagation of steady pressure, temperature and velocity distortion through multistage axial compressor. The validity of our new model is demonstrated by comparing the numerical results with those of blade row model,as shown in Figs. 1 through 5 of the full paper. Weaker attenuation of total pressure distortion through the compressor stage is obtained by moving working points from design condition to stability limit line, as shown in Fig. 9 of the full paper.