采用试验的手段,对研制的板式结构回转换热器内颗粒的传热性能进行研究,开发了一套筒体外径为273 mm、长度1 m的小型板式回转换热装置试验平台.试验采用电加热的方式,选用平均粒径dp=2 mm的石英砂作为试验颗粒,分析了填充率F=10%、电加热功率250 W的情况下,颗粒层传热性能随转速的变化规律.研究表明,试验初期颗粒层平均温度及加热板壁面温度都随着试验时间的推移呈上升趋势,且加热板壁面温升较快,随着颗粒层平均温度与加热板壁面温差逐步减小,传热系数在平均值的±25%范围内波动.在恒定加热功率的条件下,颗粒层平均温度随着转速的增加而升高,随着试验时间的推移,颗粒层的平均温升趋势也变得缓慢.转速的提高强化了颗粒层与加热板之间的热量传递,颗粒层与加热板间的传热系数和有效传热系数都随着转速的提高呈线性增长.%The heat transfer between the heating plate wall surface and the particles in a rotary heat exchanger was experimentally investigated. A set of experimental apparatus was developed and a plate rotary heat exchanger with a diameter of 273 mm and a length of 1 m was employed.The electrical heating was applied during the experimental process with quartz sands of diameter dp=2 mm as filling material and the experiments were carried out under identical filling degree ( F=10%) and heating power ( P=250 W) ,while the rotating speed was varied. Results indicated that both the surface wall temperature of the heating plates and the average bed temperature of quartz sands were increased with the prolongation of time,and the increasing rate of the former was faster. The temperature difference was gradually reduced and the heat transfer coefficient varied within the fluctuation range of ± 25%. The average bed temperature increased with the increasing of rotary speed,but the trend became more slowly as experimental time went on.The increase of rotary speed enhanced the heat transfer between the quartz sands and heating plates, both the heat transfer coefficient and efficient heat transfer coefficient were linearly increased for the increase in rotating speed of plate rotary heat exchanger.
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