相变蓄冷保温箱的模拟仿真与实验

Numerical Simulation and Experimental Investigation of Storage Box Using Phase Change Materials

摘要: 利用一种新型低温相变材料制作可以长时间维持低温的保温箱，测试新材料保冷性能并用模拟与实验对比探究低温材料的融化规律。利用自制保温箱做了空载实验，并利用ANSYS Fluent软件对空载箱内温度分布做出模拟。结果表明保温箱内上层蓄冷剂较快融化，底层维持低温时间较长，中间底面温度维持低温较久；底面模拟温度曲线与实验一致，中间温度差别大因为现实中存在自然对流热空气上浮，使得中间温度高于底面温度。利用ANSYS Fluent软件对箱内温度分布做出模拟，模拟温度曲线与实验一致，模拟得出蓄冷箱内部的融化一般是从边角开始，需要优化边角结构。因为有漏热存在，实验温度分层严重，而模拟因为条件理想化，不存在漏热，所以温度分布均匀，基本不存在分层。

Abstract: An insulated box was made from a new type of low temperature phase change material (PCM)., which is to test the thermal performance of this new type PCM and find the melting law of the PCM in this box . The no-load experiment was carried out with the self-made box. The results show that the proportion of the PCM in the upper layer can be increased because of the rapid melting of the PCM in the upper layer. The heat transfer model can ensure the cold storage time to meet people’s needs and also can be applied to the cold chain logistics system. ANSYS Fluent software was used to simulate the temperature variation of the box. The simulation results show that the bottom tem-perature curves are in agreement with the experimental results and consistent. There is a big dif-ference in the intermediate temperature because there is natural convection of hot air in the reali-ty rising so that the intermediate temperature is higher than the bottom temperature. The PCM’s melting inside the storage box usually starts from the corner and the corner structure needs to be optimized. Due to the presence of heat leakage, the experimental temperature is seriously strati-fied. However, in the simulation, the temperature distribution is uniform and there is basically no stratification because of idealized conditions and no heat leakage.