变壁温水平圆管内接触熔化新析

New Analysis of Close-contact Melting Inside a Cylinder Tube with Non-isothermal Wall

对变壁温水平圆管内接触熔化过程进行了研究.通过求解液膜边界层的控制方程,得到熔化速度的准确解析表达式,纠正了文献[10]存在的错误.熔化的理论分析结果同样适用于定壁温水平圆管内接触熔化问题.分析了管壁温度分布的影响规律,研究发现:管壁温度分布多项式的一次项对熔化影响显著;Ste数较小时(Ste<0.2),增加圆管内壁温度是缩短完全熔化时间的有效方法;Ste数较大时,改变圆管内壁温度分布对加强熔化,缩短完全熔化时间更为有效.结果对热储能系统的设计和研究具有一定参考价值.

Close-contact melting inside a cylinder tube was investigated. The correct velocity equation was obtained by solving control equations of melt layer, and the error in literature [ 10 ] was corrected. The results obtained in this paper can also be applied to solve the problem of close- contact melting with isothermal wall. The effects of temperature distribution which can be described by a muhinomial with Φ on melting process were studied, and the results indicated that the changing of coefficient c, in the function（ Tw = Tw0 [ 1 ＋ c1 （ Φ/ΦA ） ] ） had great effect on melting. For Ste 〈 0. 2, the best way to shorten complete melting time is increasing Ste number. However, for Ste 〉10. 2, it is the better way to vary the temperature distribution of wall. These conclusions are important for the design and investigation of thermal storage systems.