钙基热化学储热反应器传热传质协同强化及储热特性研究  

Synergistic enhancement of heat and mass transfer and heat storage characteristics in calcium-based thermochemical heat storage reactors

作　　者：孙霄龙 龚海艇 陈臻 王振 黄荣 刘向雷 SUN Xiaolong;GONG Haiting;CHEN Zhen;WANG Zhen;HUANG Rong;LIU Xianglei(College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,Jiangsu,China;Taizhou Power Generation Company Limited,National Energy Group,Taizhou 225327,Jiangsu,China)

机构地区：[1]南京航空航天大学能源与动力学院,江苏南京211106 [2]国家能源集团泰州发电有限公司,江苏泰州225327

出　　处：《储能科学与技术》2025年第3期1198-1209,共12页Energy Storage Science and Technology

基　　金：国家重点研发计划(2023YFE0105300);江苏省科技项目(BE2022024,BE2022602)。

摘　　要：热化学储热技术具有储热密度高、热损失低及储热时间长等优点,已成为目前储热技术领域的研究热点。然而目前针对热化学储热过程的多物理场耦合研究相对较少,并且传统固定床反应器的传热传质性能较差,这导致反应器内热化学储热过程的反应速率较低。本研究基于能量守恒方程、质量守恒方程、动量守恒方程及化学反应动力学方程等建立了多物理场耦合的CaCO_(3)分解热化学储热过程模型,针对CaCO_(3)分解热化学储热过程进行了二维非稳态数值模拟研究,详细阐述了固定床反应器中CaCO_(3)分解热化学储热过程的能量转化机理。本研究分析了反应器内储热过程的温度、转化率、反应速率等指标随时间的变化过程,并讨论了孔隙率、入口气体流速和固体反应物热导率等反应条件对储热过程的影响。模拟结果表明,增大孔隙率、提高入口气体流速、提高固体反应物热导率均可以提高CaCO_(3)分解热化学储热过程的反应速率。通过在反应器内添加具有高渗透性的高热导率多孔通道,实现了反应器传热传质特性的协同强化,使反应器储热时间缩短45.09%,反应器的压降由87735 Pa大幅降低至10 Pa。本工作为高功率密度热化学储热反应器的设计和优化提供了重要的参数依据和指导。Thermochemical heat storage technology,known for its high heat storage density,low heat loss,and long storage duration,has become a research focus in heat storage.However,limited research exists on multiphysics coupling during thermochemical heat storage,and traditional fixed-bed reactors exhibit poor heat and mass transfer performance,leading to low reaction rates.This study establishes a multiphysics coupling model for the thermochemical heat storage process of CaCO_(3) decomposition based on equations such as energy conservation,mass conservation,momentum conservation,and chemical reaction kinetics.A two-dimensional unsteady-state numerical simulation was conducted to analyze the energy conversion mechanism of CaCO_(3) decomposition in fixed-bed reactors.The study examined the temporal evolution of indicators such as temperature,conversion rate,and reaction rate during the heat storage process and discussed the impact of reaction conditions,including porosity,inlet gas flow rate,and solid reactant thermal conductivity,on the heat storage process.Simulation results indicated that increasing porosity,inlet gas flow rate,and solid reactant thermal conductivity enhanced the reaction rate of the CaCO_(3) decomposition process.By incorporating a permeable high-thermal-conductivity porous channel into the reactor,a synergistic improvement in heat and mass transfer characteristics was achieved,reducing the reactor's heat storage time by 45.09%and pressure drop from 87735 to 10 Pa.These findings provide crucial parameters and guidance for designing and optimizing highpower-density thermochemical heat storage reactors.

关 键 词：热化学储热 数值分析 CaCO_(3)/CaO 固定床反应器 

分 类 号：TK02[动力工程及工程热物理]