某系统散热器用热管传热性能试验研究

Experimental Study for the Heat Transfer of Heat Pipe used as Heat Sink for Metro Vehicle Traction Drive System

针对某工程使用的热管散热器传热性能的影响因素进行了分析,发现充液量是决定热管散热器换热性能的关键所在。为此,对Nusselt(努塞尔特)竖壁膜状冷凝理论解进行了修正和补充,从而得出适合工程应用的理论计算式。依据此式计算出某地铁牵引系统热管散热器的理论充液量应为2.85 g,再按国家标准规定的热管传热性能试验方法对不同充液量的热管进行研究,得出了额定功率下散热器热阻随充液量变化的规律。经分析认为,散热器的最佳充液量为3g,该结果经试验证明与理论计算一致。同时通过对该充液量热管进行传热极限试验,证明3 g的充液量不仅具有适当的设计余量,还可以保证地铁系统出现过载工况时系统的运行可靠。

Gravity heat pipe heat sink cooling technology is preferred for metro vehicle traction drive system. This paper first analized the factors affecting the heat transfer capability of the heat pipe as a heat sink for a subway,and it was found that the liquid filling is the key to the performance of a heat pipe. Then the Nusselt vertical wall film condensation theory formula was corrected to be suitable for the engineering application,and used to determine the filling quantity of metro traction system radiator with heat pipe,which was calculated at 2. 85 g. Additionally,according to the national standard test method for heat pipe,heat transfer performance of different filling quantities of heat pipe were studied,and the thermal resistances with different liquid filling amount were obtained under rated power. The optimum filling amount was then determined to be 3 g through the analysis of experimental data,indicating the good agreement between test results and theory calculation. Meanwhile,the heat transfer limit test verified that the 3 g filling amount has an appropriate design margin and can ensure the traction system reliability under overload conditions.