回路热管传热特性的测试与分析

Test and analysis on heat transfer performance of the loop heat pipe

回路热管(LHP)是一种利用工质蒸发和冷凝的相变传递热量的高效传热装置。为研究LHP的换热特性,制作了简单的LHP传热性能测试装置。LHP原材料采用不锈钢,工质为二次蒸馏水,毛细吸液芯为500目的铜丝网。实验研究了热负荷及倾斜角度对回路热管传热特性的影响,结果表明,LHP的启动时间和阻值随着加热功率的增加而降低,而随着倾斜角度的单调增大,LHP的启动时间和阻值则呈现先减小后增大的趋势,表现出优越的传热特性。研究结果为LHP在不同安装场合条件下的运用提供一定的实验依据,同时也为现代电子设备散热问题提供了的一种解决途径。

Loop heat pipe （LHP） is a heat transfer device which mainly relies on the evaporation and condensation of a working fluid to realize heat transport and uses the working fluid capillary force and vapor pumping force to ensure the fluid circulation. A simple experimental setup was built to test the heat transfer performance of the miniature loop heat pipe. The loop heat pipe is made of stainless steel with copper mesh wick and secondary distilled water as the working fluid. Heat transfer characteristics of the loop heat pipe under different heating loads, inclination angles are studied experimentally. Results show that the start-up characteristics and thermal resistance of loop heat pipe are related to the heat load and the inclination angle. When the heat load increases, the start-up time is short and the thermal resistance is also reduced. But the start-up time and the thermal resistance decrease at first, but then increase, as the inclination angle increases. The LHP also shows good start-up characteristic and can steadily work as well. This provides reference for the practical applications of loop heat pipe sink with different installation conditions, and all these indicate that the LHP has the potential to be a good solution for cooling of modern electronics.