中文摘要：

环路热管（loop heat pipe，LHP）是一种靠蒸发器内毛细芯产生毛细力驱动回路运行，利用工质相变来传递热量的高效传热装置。研制了一套小型平板式蒸发器、风冷式冷凝器的环路热管（mLHP），mLHP的毛细芯为500目不锈钢丝网，工质为丙酮和甲醇。蒸发器、冷凝器以及所有管路均由紫铜制成。着重研究了平板型mLHP在不同热负荷条件下的温度波动特性。实验结果表明，平板式mLHP在某些热流密度区间容易发生温度波动；同时，重点研究了工质对mLHP系统温度波动的影响，并给出相应的合理解释。

英文摘要：

Loop heat pipes （LHPs） are heat transfer devices whose operating principle is based on the evaporation and condensation of a working fluid, and use the capillary pumping forces to ensure the fluid circulation. A series of tests were carried out with a miniature loop heat pipe （mLHP） with flat evaporator and a fin-and-tube type condenser. The loop was made of pure copper with stainless mesh wick and acetone as the working fluid. At some low heat loads, temperature oscillations were observed throughout the loop. Detailed study was conducted on the characteristics of temperature oscillation of the flat mLHP at various heat fluxes. It is expected that the compensation chamber is the most critical component of the mLHP, Its hydrodynamic state decides the extent and the characteristics of the temperature oscillations for the input heat load. The heat leaks from the evaporator to the compensation chamber, the heat loss to ambient and the subcooled liquid temperature decides the vapor condition inside the compensation chamber, and the rate of vapor growth or dissipation controls the nature of the temperature oscillation. The effects of different working fluid to the temperature oscillations were studied in detail.