有限长偏心转静微小间隙流动及对流换热实验  

Experiment for flow field and convective heat transfer between rotor and stator with finite length at high rotational speed

作　　者：刘源 吕元伟 马兆坤 张镜洋 王佳俊 LIU Yuan;LYU Yuanwei;MA Zhaokun;ZHANG Jingyang;WANG Jiajun(College of Astronautics,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China)

机构地区：[1]南京航空航天大学航天学院,南京211106

出　　处：《航空动力学报》2024年第12期287-296,共10页Journal of Aerospace Power

基　　金：航空基金(201928052008);国家自然科学基金(52206091);江苏省自然科学基金(BK20210303)。

摘　　要：为获得转静微间隙内旋转、剪切、偏心等多效应相干下的热流动变化规律,建立其流动与换热特性测试方法及装置,对间隙比为0.024的转静微小间隙在旋转雷诺数为0~980、偏心率为0~0.6范围内的全向压力与传热系数分布进行实验研究。结果表明,间隙内存在自作用的轴向与轴向压差以及压差作用下的端泄效应,气膜压力沿轴向由中心截面向轴端逐渐降低、周向近似正弦分布,最大正压值和最大负压值分别位于距最小间隙上游0.22π和下游0.24π区域附近;静子表面换热受离心力强化的自然对流和剪切流动的双重作用,随旋转雷诺数增大表面传热系数由不均匀分布而逐渐变得均匀,且由于剪切流动的增强而表面传热系数逐渐变大。与同轴状况相比,偏心时最小间隙处的平均表面传热系数最大增强49.0%。In order to obtain the thermal flow variation law of the rotation,shearing,eccentricity and other multi-effect coherence in the rotating static micro-clearance,the test method and device for the flow and heat transfer characteristics were established.The omnidirectional pressure and heat transfer coefficient distribution of the rotating Reynolds number of 0—980 and eccentricity of 0—0.6 in the rotating static micro-clearance with clearance ratio of 0.024 were experimentally studied.The results showed that there was a self-acting axial and axial pressure difference as well as end leakage effect under the pressure difference.The gas film pressure gradually decreased from the central section to the axial end along the axial direction,and the gas film pressure was approximately sinusoidal in the circumferential direction.The maximum positive pressure and maximum negative pressure were respectively located near the region 0.22πupstream and 0.24πdownstream the minimum gap.The heat transfer on stator surface was influenced by both natural convection and shear flow strengthened by centrifugal force,and the distribution of convective heat transfer coefficient gradually became uniform from non-uniform with the increase of rotational Reynolds number,and the convective heat transfer coefficient gradually increased with the increase of shear flow.Compared with the coaxial condition,in case of eccentricity,the average convective heat transfer coefficient increased by 49.0%at the minimum gap.

关 键 词：剪切流动 压力测量 对流换热测量 小尺度间隙 高转速 端泄效应 

分 类 号：V211.71[航空宇航科学与技术—航空宇航推进理论与工程]