Abstract Over the past decade, DEM-based simulation has become a promising alternative to physical measurements of thermal particulate systems. Despite their rapid advancement and successful applications to a wide range of industrial processes, a comprehensive review of the theory that underpins the thermal DEM-based simulations is yet to be conducted. This work presents a critical and in-depth review of all major thermal models and heat transfer mechanisms pertinent to DEM-based simulations. Other critical aspects such as boundary conditions and particle body temperature distribution that were often overlooked are also summarised and discussed, aiming to provide a clear path for the development of robust thermal DEM-based models. The quasi-analytical solution based on the Hertzian contact theory proves classic and remains the main method to solving the conduction of static contacts. Recent attempts have been mainly directed towards improving the calculation of conduction through collisional contacts and the thin wedge of interstitial fluid between particles. Empirical correlations that were developed before 1981 remain predominant in calculating the fluid-particle convection coefficient. Though more accurate, the discrete models of radiation that rely on the solution of view factors amongst individual particles have been applied much less than the continuum models due to the significant computational overhead. Generally, previous efforts have led to the construction of a solid framework of thermal DEM-based models. Significant work is required to improve existing or develop new heat transfer sub-models, particularly those for accurate and efficient modelling of conduction and radiation in particle-laden systems.

中文翻译：

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基于离散元方法 (DEM) 的热过程模拟中的传热建模：理论和模型开发

摘要 在过去的十年中，基于 DEM 的模拟已成为热颗粒系统物理测量的有前途的替代方案。尽管它们迅速发展并成功应用于广泛的工业过程，但尚未对支持基于热 DEM 的模拟的理论进行全面审查。这项工作对与基于 DEM 的模拟相关的所有主要热模型和传热机制进行了批判性和深入的审查。还总结和讨论了其他关键方面，例如边界条件和粒子体温分布，这些方面经常被忽视，旨在为开发基于热 DEM 的稳健模型提供清晰的途径。基于赫兹接触理论的拟解析解被证明是经典的，并且仍然是解决静接触传导的主要方法。最近的尝试主要针对通过碰撞接触和粒子之间的间隙流体的薄楔来改进传导的计算。1981 年之前开发的经验相关性在计算流体粒子对流系数时仍然占主导地位。尽管更准确，但由于计算开销很大，依赖于单个粒子之间视角因子解的离散辐射模型的应用远少于连续模型。一般来说，之前的努力已经导致构建基于热 DEM 的模型的坚实框架。