移动式相变蓄热系统数值模拟与优化

NUMERICAL SIMULATION AND OPTIMIZATION OF MOBILE PHASE CHANGE HEAT STORAGE SYSTEM

以移动式相变蓄热系统为研究对象,通过Fluent软件对其蓄热器进行仿真模拟,分析相变材料蓄热和放热过程中蓄热器内部温度场、固液界面和液相体积比例随时间的变化过程,并对其进行优化。结果表明:相变材料熔化蓄热过程中系统上部分速度快,呈"梨形"结构,但系统内两侧以及底部蓄热过程中存在"死区";通过改变管径大小及数量和添加翅片的方法可提高蓄热系统的换热效率,破除蓄热瓶颈,为移动式蓄热技术和余热利用的研究提供理论依据。

With mobile phase change heat storage system as the research object,the numerical simulation is made to the heat storage through fluent software. The variation of the internal temperature field,the solid liquid interface and the ratio between solid and liquid phase mass with time are analyzed and optimized during the PCM heating storage and heat releasing processes. The results show that in the process of melting heat storage,the melting speed of the upper part of system is faster. The melting part shows a pear shaped structure. But the "dead zones" exists at the both sides and bottom of system. However,the heat transfer efficiency can be improved through changing pipe diameter,pipe quantity and adding finned in the pipes,This work is useful to getting rid of heat storage bottleneck and providing theoretical basis for mobile heat storage technology and waste heat utilization research.