论文部分内容阅读
为了研究通孔金属泡沫内嵌相变材料凝固过程特性规律及泡沫材料孔结构参数对凝固过程的影响,搭建了固液相变传热可视化测量系统,利用该系统就通孔铜泡沫强化蓄冰过程开展了实验研究。实时观测了凝固相界面的瞬态移动过程,测量了金属骨架表面和内嵌相变介质的实时温度,研究结果表明:铜泡沫可有效改善蓄冰后期传热恶化现象,大幅减少蓄冰时间,加入铜泡沫后,结冰所需时间与纯水工况相比减少为48.86%(孔密度为1181m-1,孔隙率为0.90)和60.97%(孔密度为1181m-1,孔隙率为0.97);铜泡沫的孔隙率对结冰过程影响较大,孔隙率为0.90的铜泡沫比孔隙率为0.97的铜泡沫中水完全凝固时间减少20%,而孔密度对结冰过程影响可忽略不计。可视化结果表明,未凝固相局部自然对流导致凝固相界面发生倾斜,呈现下部略快于上部的凝固界面。
In order to study the characteristics of the solidification process of the through-hole metal foam embedded phase change material and the influence of the pore structure parameters of the foam on the solidification process, a visualization measuring system of solid-liquid phase transition heat transfer was established. By using this system, The process of experimental research. The transient movement of the solidified interface was observed in real time. The real-time temperature of the metal matrix and the phase-change medium were measured. The results show that the copper foam can effectively reduce the heat transfer deterioration in the late ice storage, greatly reduce the ice storage time, The addition of copper foam reduced the time required for icing to 48.86% (porosity 11.81 m -1, porosity 0.90) and 60.97% (pore density 1181 m -1, porosity 0.97) compared to pure water conditions The porosity of copper foam greatly affects the icing process. The copper foam with porosity of 0.90 is 20% less than that of the copper foam with porosity of 0.97. The influence of pore density on icing process is negligible. The visualization results show that the natural convection of the uncoagulated phase leads to the tilting of the solidified phase interface, showing the solidified interface at the lower part slightly faster than the upper part.