螺旋管外相变微胶囊悬浮液换热-蓄热特性提升的影响分析  

Influence analysis on natural convective heat transfer and storage characteristics of mPCM slurry outside helical coiled tube

作　　者：夏鹏 徐国英[1] 陈麒 杨颖 张小松[1] XIA Peng;XU Guoying;CHEN Qi;YANG Ying;ZHANG Xiaosong(School of Energy and Environment,Southeast University,Nanjing 210096,China)

机构地区：[1]东南大学能源与环境学院,江苏南京210096

出　　处：《中南大学学报（自然科学版）》2022年第2期696-706,共11页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51676046)。

摘　　要：为了探究相变微胶囊悬浮液在蓄热器中瞬态自然对流换热及蓄热特性,建立含垂直螺旋盘管的沉浸式蓄热箱的三维数值模型,并通过均一相模型模拟螺旋管外相变微胶囊悬浮液非稳态蓄热过程的温度场、速度场以及换热系数的变化规律,探究微胶囊颗粒质量分数和螺旋管结构对其换热、蓄热特性的影响。研究结果表明:悬浮液蓄热过程具有较高的自然对流换热系数,其换热效果明显比块状纯石蜡固-液相变换热效果好;颗粒质量分数增加虽使自然对流换热性能有所降低,然而相较于基液而言,颗粒质量分数为30%的悬浮液蓄热量提升了约54.4%;当螺旋管节距为0.15 m和弯曲直径为0.20 m时,换热和蓄热性能综合达到最优。In order to explore the transient natural convective heat transferred and storage performances of microencapsulated phase change material(mPCM) slurry,a three-dimensional numerical model of an immersed heat storage tank containing a vertical helical coiled tube was established.The homogeneous phase model was used to simulate the temperature field,velocity field and the heat transfer coefficient variation.The effects of particle concentrations and structure parameters on its heat transfer and storage performances were also discussed.The results show that the heat transfer coefficient of mPCM slurry is dramatically larger than that of pure paraffin.Although the increase in particle concentrations reduces its heat transfer performance,the heat storage capacity of mPCM slurry with 30% particle mass fractions increases by 54.4% compared with base fluid.The heat transfer and storage performances can be overall optimized when the pitch is 0.15 m and the bending diameter is 0.20 m.

关 键 词：数值模拟 相变 螺旋换热管 自然对流 传热 蓄热 

分 类 号：TK124[动力工程及工程热物理—工程热物理]