Melting behavior and heat transfer characteristics of water-insoluble material immersed in water.

This paper presents the melting behavior and heat transfer characteristics of a water-insoluble material immersed in water. N-hexadecane, popularly used as a phase change material, is adopted as a water-insoluble material. A rectangular n-hexadecane solid is placed vertically in the water. The melting behavior of n-hexadecane and its melting rate are then observed under a variety of water temperature conditions in the test vessel. An evaluation of the melting behavior and the local heat transfer coefficient indicates that the ambient water flow along the vertical n-hexadecane block enhances heat transfer at the upper side of the block as the ambient water temperature becomes lower. The upward flow of the melting liquid prevents the melting heat transfer at the upper part of the block as the ambient water temperature becomes higher. The variation of the shape of the top part of the block then changed and the heat transfer coefficient barely decreased when Polyoxyethylene Sorbitan Monooleate (Tween 80) was added in the water.

本文针对浸没于水中的水不溶性材料的熔融行为与传热特性展开研究。研究选取广泛用作相变材料（phase change material）的正十六烷（n-hexadecane）作为受试的水不溶性材料。将长方体固态正十六烷垂直放置于试验容器的水中，在多种水温条件下观测正十六烷的熔融行为及其熔融速率。通过对熔融行为与局部传热系数的评估可知：当环境水温较低时，沿垂直正十六烷块体流动的环境水流可强化块体上侧的传热过程；当环境水温较高时，熔融液体的向上流动则会抑制块体上部的熔融传热。在水中加入聚氧乙烯山梨醇酐单油酸酯（吐温80，Polyoxyethylene Sorbitan Monooleate (Tween 80)）后，块体顶部的形状发生变化，且传热系数几乎未出现下降。