侧载及加热方位对槽道内临界热流密度影响  

Influences of side load and heating orientation on critical heat flux in a rectangular groove

作　　者：李冈[1] 宋保银[1] 张钊[1] 王洪[1,2] 宋军辉[1] 

机构地区：[1]南京航空航天大学航空宇航学院 [2]中国人民解放军69008部队

出　　处：《航空动力学报》2016年第1期203-210,共8页Journal of Aerospace Power

基　　金：国家自然科学基金(50576035);高等学校博士学科点专项科研基金(20040287017);江苏高校优势学科建设工程资助项目

摘　　要：为了研究侧载以及加热方位对矩形窄缝槽道内临界热流密度特性的影响,在旋转平台上进行了两相流的超重力实验.以蒸馏水为工质,通过改变质量流速、入口温度、侧载大小以及加热方位,获得了发生临界换热现象时的质量流速、实验段压降和壁温的变化趋势,考察了侧载和加热方位对临界热流密度的影响规律,并对侧载下两相流不稳定性进行了简析.实验表明:发生临界换热时,壁温迅速上升,有效加热热流开始减少,关闭加热电源后,实验段压降下降、质量流速回升较明显;侧载以及不同的加热方位对临界热流密度有明显影响;临界热流密度发生前后,蒸汽回流导致进口温度上升,增加了流动的不稳定性.An experimental investigation into the effects of side load and heating orienta- tion on the critical heat flux of flow boiling in a narrow rectangular groove was performed with a rotational platform. Using distilled water as working fluid, the change trend of mass velocity, the pressure drop in test section and its outlet wall temperature before and after reaching critical heat flux were obtained, the effects of side load and heating orientation on critical heat flux were investigated at different mass velocities, inlet temperatures, dynamic loads and heating orientations. Flow instability was briefly analyzed. The results show that in addition to the rapid wall temperature rise, the effective heat flux decreases as the critical heat transfer occurs. The pressure drop in test section decreases and mass velocity rebounds obviously after power cutoff. The effects of side load and heating orientation on critical heat flux are obvious. Not soon before and after the critical heat transfer occurs, the back flowing vapor increases the inlet fluid temperature, thus enhancing the flow instability.

关 键 词：侧载 加热方位 窄缝槽道 流动沸腾 临界热流密度 

分 类 号：V245.3[航空宇航科学与技术—飞行器设计] TK124[动力工程及工程热物理—工程热物理]