联箱式分离型热管的多支管并联可能导致流量分配不均，造成部分管道干涸，降低换热效果。搭建了7根管道并联的U型联箱式分离型热管实验平台，以R134a为工质，在800~2 200 W加热功率下，分析热管高效工作的充液率上下限、最佳充液率、热管系统换热特性及管道流量分配。结果表明：热管在充液率为31%~46%时可正常工作，最佳充液率约为42%；确认了各换热支管出现的流量分配不均匀特征，最靠近入口的分支管换热性能最佳，第4~6根换热管流量分配最少、性能最差。

The parallel channels in manifold of separated gravity heat-pipe may have the problem of the uneven distribution of flow,which can even lead to dry pipe and reduce the heat transfer effect.A U-type separated gravity heat-pipe system with 7 parallel channels has been built,R134a is chosen as the medium and the heating power is changing from 800 W to 2 200 W.The upper and lower limits of the liquid filling rate,the optimum liquid filling rate,the heat transfer characteristics of the heat pipe system and the distribution of the flow are studied.Results show that the heat pipe can work steadily with the liquid filling rate of 31%~46% and the optimum liquid filling rate is about 42%,and the characteristics of uneven distribution of flow in channels have been confirmed.The tube1 has the best heat transfer efficiency,while the flow distribution and heat transfer performance in tubes 4~6 is not satisfactory.

TK172.4

科技部重大专项（2015ZX06004002）