The structure and characteristics of the two-phase closed thermosyphon with working trap are described. A mathematical model is presented to calculate the unsteady-state start-up process of a room temperature heat pipe. The model is based on the special structure and operation conditions of the heat pipe, which is simplified to that the steam temperature in the tube changes with time only. The relation of steam temperature and time is obtained by numerical calculation and used as the temperature boundary condition of the measurement trap. The temperature, velocity and pressure distribution in the working trap are then solved by FLUENT. The main effect of ambient air on the thermometer well occurs at the orifice, while the temperature is uniform at other locations. The calculation is in good agreement with experimental data, and the maximum deviation is 3. 7 K when the start-up time is 100 s. The simulation and experiments indicate that water fluid filling volume has little effect on the start-up performance of the heat pipe. The mathematical model and the research methods provide a new approach for the study of special heat pipes.%介绍了一种具有工作阱的两相闭式热虹吸管的结构和特点.通过观察实验,将热虹吸管的启动模型简化为蒸汽温度只随时间变化的非稳态模型,通过数值计算求解热虹吸管内蒸汽随时间的变化关系.将热虹吸管的工作阱作为研究对象,数值计算得到的温度响应作为工作阱的温度边界条件,利用FLUENT求解工作阱内温度及压力分布.结果显示计量阱内除管口位置外具有良好的等温特性.将模拟值与实验值进行比较,计算值和测量值吻合较好,最大偏差出现在响应时间为100 s左右,温度偏差为3.7K.模拟和实验均证明工质充灌量对具有工作阱的两相闭式热虹吸管的启动性能影响不大.
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