叶栅端壁附面层叶片力亏损预测模型

本文基于实验结果,提出了一种预测轴流压气机叶栅端壁附面层叶片力亏损的通用模型.该模型的理论性强、物理意义明确.它包含了目前广泛使用的现有诸种叶片力亏损模型且明显减少了模型的经验性.应用于不同轴流压气机叶栅端壁附面层流动的数值分析结果与实验结果的比较表明,本文所建立的新模型通用性更强且精度也得到了进一步的提高.

On Model for Predicting Blade Force Defect in End Wall Boundary Layer Inside Axial Compressor Cascade

The authors in previous papers1,2] found it necessary to replace 2-dimensional model with3-dimensional model for predicting blade force defect in end wall boundary layer inside axial compressorcascade.But the model in Refs.1,2] depends on several empirical constants and good precision of com-puted results is unattainable.The aim of this paper is to reduce empiricism and to attain good precision.An experimental compressor cascade and a minute five-hole probe are designed by the authors.Themeasurements of the end wall flow field inside the experimental cascade are made by five-hole probe con-trolled by grating instrument.Two conclusions drawn from experimental results are:(1)the cause of the blade force defect in the end wall boundary layer is that the static pressure dis-tribution along thickness of boundary layer near the pressure surface is different from that near the suc-tion surface (Fig.2 in the full paper).(2)blade force defect D_(?) is positive and varies greatly from the inlet to outlet of the cascade.Based mainly on above two conclusions,a new model is established to predict blade force defect.Comparison of calculations based on the new model with experimental data from different axialcompressor cascades in this paper and in Refs.3-6] shows that the new model gives results higher in preci-sion than those of all previous models.The numerical results also show that the authors' function ofentrainment (eq.21 in the full paper) must be used when the shape factor is larger than 1.6.