Abstract The horizontal rotary retort is one of the important equipment in oil shale retorting by solid heat carrier technology, in which the heating of oil shale plays a crucial role in shale oil production. In this work, a comprehensive heat transfer model including both conduction and radiation under contact and non-contact conditions was proposed to numerically investigate the heat exchange among particles at five different pathways by employing the discrete element method (DEM). The effects of particle physical parameter (particle size) and operating conditions (rotational speed and fill ratio) on thermal characteristics such as oil shale heating time, thermal rate, thermal index and heat flow were deeply analyzed. In summary, the heat flow generated by particle-fluid-particle heat conduction contributed 66–71% of the total heat flow, the radiative flow produced by particle-particle heat radiation was 22–30%, and the thermal contribution of particle-particle heat conduction was the least, accounting for only 6–7%.

中文翻译：

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卧式旋转罐中颗粒间传热机理的研究

摘要 卧式回转罐是固体热载体技术油页岩干馏的重要设备之一，其中油页岩的加热在页岩油生产中起着至关重要的作用。在这项工作中，提出了一个包括接触和非接触条件下的传导和辐射的综合传热模型，通过采用离散元法（DEM）数值研究了五种不同路径下颗粒之间的热交换。深入分析了颗粒物理参数（粒径）和操作条件（转速和填充比）对油页岩加热时间、热速率、热指数和热流等热特性的影响。总之，粒子-流体-粒子热传导产生的热流占总热流的 66-71%，