基于微重力条件下的导热控制微分方程，采用焓法建立热管吸热器相变蓄热单元计算模型，对微重力条件下热管吸热器蓄热容器的相变传热过程进行了模拟计算，分析了空穴率对蓄热容器内部的温度场和热性能的影响。结果表明：经与美国国家航空航天局(NASA)方案进行比较，所建立的计算模型合理、准确，能够较好地模拟热管吸热器蓄热单元蓄、放热过程；热管吸热器壁温与相变蓄热容器温度非常接近，包含着相变材料的整个热管起着均匀热负荷的作用，与基本型吸热器相比热管吸热器相变材料熔化率大幅提高，相变材料利用率较高；随着空穴率的增大，相变材料利用率降低，相变材料容器的蓄热能力降低，同时相变蓄热容器内温度梯度增大，可能导致该处热应力过大，从而降低其使用寿命。%On the basis of thermal conduction differential equations under microgravity condition,the enthal-py method was applied to establish calculation model for phase change heat storage unit in heat pipe receiv-ers.Considering both the void cavity and phase change,numerical simulation was carried out.The effects of void cavity on temperature field and thermal performance of the phase change material (PCM)canister were investigated.The results show that,compared with the National Aeronautics and Space Administra-tion (NASA)results,the established model is reasonable and accurate,which can well simulate the heat storage and release process of the PCM canister.The wall temperature of the heat pipe receiver is close to that of the PCM canister,implying the entire heat pipe containing PCM plays a role in heat load uniformi-ty.The maximum melting rate of the PCM is 92%,indicating the utilization efficiency of the PCM is high. With an increase in void cavity,the unmelted PCM amount increases in the area close to the void during the last stage of solar radiation and the unconsolidated PCM amount increased during the last stage of shadow, indicating the PCM's utilization efficiency decreased and the PCM tank's heat storage capability reduced. Moreover,the temperature gradient in the PCM heat storage tank increased,which may cause over high thermal stress,leading to a decrease in the tank's service life.
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