摘要
为了探究颗粒堆积结构变化对近壁面颗粒传热过程的影响,构建了近壁面两颗粒的非稳态传热模型,研究了不同初始温度条件下颗粒组合角度变化对近壁面颗粒传热特性的影响规律。结果表明:初始温度越高,所需换热时间越长,颗粒组合角度增加,使得换热时间明显减少。初始温度为1 073.0 K时,换热面平均热流密度值呈先迅速下降后缓慢下降的趋势。同一时刻,组合角度越大,颗粒平均温度越低。不同组合角度颗粒的固相传热率均达到0.80以上。颗粒组合角度越大,固相传热占比越小,辐射传热占比越大。在换热前期,辐射传热率最高可达0.57,对传热过程的影响不可忽略。
In order to investigate the effect of the change of particle stacking structure on the heat transfer process of the particles near the wall, an unsteady heat transfer model of two particles near the wall was established, and the effect of the particle combination angle on the heat transfer characteristics of the particles near the wall was studied. The results show that with the increase of the combination angle, the decrease rate of the particles enthalpy increases, the heat transfer time decreases, the decrease rate of the average temperature of the particles and the decrease rate of the solid-phase heat flux increase significantly, and the gas-phase heat flux is greatly affected by the heat transfer area.The cos function fitting formula of combined angle and heat transfer time is obtained. When the initial temperature is 1 073.0 K the average heat flux of the heat exchange surface decreases rapidly first and then slowly. With the increase of heat transfer time, the solid-phase heat transfer rate reaches above 0.80. The larger the particle combination angle, the smaller the solid phase heat transfer rate and the greater the radiation heat transfer rate.In the early heat transfer process, the radiation heat transfer rate can reach up to 0.57, and its influence on the heat transfer process cannot be ignored.
作者
张凯
孙鹏
郑斌
徐纪国
王有镗
王振领
王全振
刘永启
ZHANG Kai;SUN Peng;ZHENG Bin;XU Jiguo;WANG Youtang;WANG Zhenling;WANG Quanzhen;LIU Yongqi(School of Transportation and Vehicle Engineering,Shandong University of Technology,Zibo 255049,China)
出处
《热科学与技术》
CAS
CSCD
北大核心
2022年第2期136-143,共8页
Journal of Thermal Science and Technology
基金
国家重点研发计划重点专项资助项目(2017YFB0603504-2)
国家自然科学基金资助项目(51806130)
山东省自然科学基金资助项目(ZR2017LEE019)。
关键词
组合角度
近壁面颗粒
余热回收
数值模拟
combination angle
particles near the wall
waste heat recovery
numerical simulation
