Comsol如何利用焓的方法处理相变问题！

dltsha

对于有相变的传热问题，我看到的都是等效比热的方法进行处理，请问是否可以利用焓的方法处理，具体如何操作？哪种方法更好？

光耀中华

用比热的
例子Continuous casting

edodo

冷 却 与 固 化
本 案 例 描 述 应 用 于 连 续 铸 造 程 序 中 的 冷 却 与 固 化 的 现 象
该案例应该对你有帮助

dltsha

谢谢edodo的资料，我以前也看过，是利用等效比热的方法来模拟的。
我现在想了解利用焓的方法模拟相变过程，不知是否有这方面的算例？

edodo

http://scholar.google.cn/scholar?hl=zh-CN&lr=&newwindow=1&q=COMSOl+phase+change+enthalpy&lr=
刚才随便在网上收缩了一篇论文，或许对你有帮助。
Numerical and experimental investigation of melting and
freezing processes in phase change material storage
Piia Lamberg a, Reijo Lehtiniemi b*
, Anna-Maria Henell b
ABSTRACT
Phase change material (PCM) storages are used to balance temporary temperature
alternations and to store energy in several practical application areas, from electronics to
the automobile industry and also buildings. In current telecommunication electronics
both portable and larger scale thermal transients that occur due to temporarily varying
power dissipation are customary. The use of PCM heat storage to compensate for
temperature peaks that may occur offer significant savings in time-dependent thermal
management in the aforementioned products.
The aim of this paper was to obtain physical validation of the numerical results
produced using FEMLAB. This validation was obtained through a comparison of
experimental data and numerical results. The numerical methods studied were an
enthalpy method and an effective heat capacity method. An ensemble of experimental
PCM storages, with and without heat transfer enhancement structures, was designed and
constructed. The numerical predictions calculated with FEMLAB simulation software
were compared to experimental data. Both numerical methods gave good estimations
for the temperature distribution of the storages in both the melting and freezing
processes. However, the effective heat capacity method, which used a narrower
temperature range, dT=2°C, was the most precise numerical method when the numerical
results were compared to the experimental results.
Keywords: Phase change materials; effective heat capacity method; enthalpy
method

zxj2008

太好了,我也正在研究相变(土壤的冻结过程)

lizongchun

有例子 发个过来啊

第二类永动机

高深啊

光耀中华

一头雾水