超临界压力航空煤油不稳定流动实验  

Experiment on flow instability of aviation kerosene under supercritical pressures

作　　者：王彦红 李素芬[2] 赵星海[1] WANG Yanhong;LI Sufen;ZHAO Xinghai(School of Energy and Power Engineering, Northeast Electric Power University,Jilin Jilin 132012,China;School of Energy and Power Engineering, Dalian University of Technology,Dalian Liaoning 116024,China)

机构地区：[1]东北电力大学能源与动力工程学院,吉林吉林132012 [2]大连理工大学能源与动力学院,辽宁大连116024

出　　处：《航空动力学报》2018年第12期2838-2844,共7页Journal of Aerospace Power

基　　金：国家自然科学基金(51576027);东北电力大学博士科研启动基金(BSJXM-2017205)

摘　　要：对竖直上升圆管内超临界压力航空煤油的不稳定流动开展了实验研究。考察了管内壁温度、质量流量、出口温度、进出口压差等参数随时间的振荡情况,阐述了不稳定流动的诱发原因和反馈机制,建立了不稳定流动临界热负荷的预测关系式。结果表明:不稳定流动工况中发现了管内壁温度和进出口压差的异常波动。边界层发展过程中传热恶化形成类气膜是不稳定流动的诱因,存在两种类型的反馈机制:一方面,类膜态沸腾和类核态沸腾交替引发恶化换热和强化换热,导致热力不稳定;另一方面,压力扰动出现声波,压缩波使类气膜厚度减小且传热改善,膨胀波使类气膜厚度增大且传热变差,导致声波不稳定。两种反馈机制的综合作用形成热声振荡现象。Experimental study on flow instability of aviation kerosene under supercritical pressure in a vertical upward circular tube was conducted.The time-dependent inside-wall temperature,mass flux,outlet temperature and inlet-outlet pressure drop oscillations were investigated.The formation reason and feedback mechanism of flow instability were expounded.The expression for critical heat load prediction of flow instability was obtained.Results indicated that the abnormal fluctuations of inside-wall temperature and inlet-outlet pressure drop occurred under the flow instability conditions.The flow instability was caused by agaslike state film,owing to the deteriorated heat transfer during the development process of boundary layer.Two types of feedback mechanism were found.On the one hand,the deteriorated and enhanced heat transfer appeared alternately due to the pseudo-film boiling and pseudo-nuclear boiling,which led to the thermal instability.On the other hand,the pressure disturbance triggered the acoustic wave,the compressed wave made a decrease in thicknessof gas-like state film,and enhanced the heat transfer,while the expandsion wave made an increase in thickness of gas-like state film,and weakened the heat transfer,leading to the acoustic wave instability.The comprehensive effects of these two feedback mechanisms cause the thermo-acoustic oscillation phenomenon.

关 键 词：超临界压力 航空煤油 不稳定流动 热力不稳定 声波不稳定 

分 类 号：V231.1[航空宇航科学与技术—航空宇航推进理论与工程]