扰流参数和非均匀颗粒结构参数对填充床相变蓄热器蓄热特性的影响  

Effect of Turbulence and Non-uniform Particle Structure on Heat Storage Performance of Packed Bed Phase-change Thermal Storage Tank

作　　者：刘赟[1] 赵旭[1] 申文然 谢凌天 LIU Yun;ZHAO Xu;SHEN Wenran;XIE Lingtian(Hebei Key Laboratory of Low Carbon and High Efficiency Power Generation Technology,Department of Power Engineering,North China Electric Power University,Baoding 071003,Hebei Province,China)

机构地区：[1]华北电力大学动力工程系,河北省低碳高效发电技术重点实验室,河北保定071003

出　　处：《动力工程学报》2023年第8期974-982,共9页Journal of Chinese Society of Power Engineering

基　　金：河北省自然科学基金资助项目(E2020502021);中央高校基本科研业务费面上资助项目(2020MS106)。

摘　　要：以填充床式相变蓄热器作为研究对象,将60%NaNO3和40%KNO3混合而成的二元硝酸盐作为传热流体,将59.98%MgCl2、20.42%KCl、19.6%NaCl混合熔盐作为相变材料,建立无需对每个封装颗粒网格离散化的多孔介质局部非热平衡模型。通过数值计算对填充床式相变蓄热器的蓄热性能进行研究,分析了扰流参数以及颗粒结构参数等对蓄热器蓄热性能的影响。为提升蓄热器的蓄热性能,采用非均匀颗粒直径分布,并与等颗粒直径进行比较。结果表明:与填充0.025 m和0.015m的等颗粒直径相比,蓄热器上端填充0.025m和下端填充0.015m的非均匀颗粒直径分布的相变材料完全融化时间分别缩短了3.81%和1.90%。Taking the packed bed phase-change thermal storage tank as the research object,a local nonthermal equilibrium model of porous medium was established without mesh discretization of each encapsulated particle.,by using the binary nitrate composing of 60%NaNO3and 40%KNO3as the heat transfer fluid,and the mixed molten salt of 59.98%MgCl2,20.42%KCl and 19.6%NaCl as the phase-change material.The heat storage performance of packed bed phase-change thermal storage tank was numerically studied,and the influence of turbulence and particle structure on heat storage performance of the thermal storage tank was analyzed.To improve the heat storage performance of thermal storage tank,non-uniform particle distribution was adopted and compared with the uniform particle distribution.Results show that compared with the uniform particle diameter of 0.025mand 0.015m,the complete melting duration of phase-change material with the particle diameter of 0.025mat the upper end and 0.015mat the lower end decreases by 3.81%and 1.90%,respectively.

关 键 词：填充床相变蓄热器 多孔介质模型 蓄热特性 扰流参数 非均匀颗粒结构参数 

分 类 号：TK512[动力工程及工程热物理—热能工程]