关键词: 颗粒尺度, 离散颗粒模型, 传热, 固定床

Abstract: Heat conduction in granular assemblies plays an important role in industrial applications. In this paper, the details of heat transfer mechanism are considered in particle scale. The conduction resistances of solid interior, rough surface, gas film between solids, and gas-gap between contacted surfaces are modeled and coupled with discrete element method to deduce a heat transfer model. Numerical simulations are performed to investigate the effects of particle diameter, specific thermal capacity, thermal conductivity of particles and compressive load on effective thermal conductivity(ETC) in fixed beds. The predicted ETC is compared with experimental and simulated data in literature, indicating that the presented model can predict ETC satisfactorily, which provides a useful tool for studying heat transfer in particle assemblies.

Key words: particle scale, discrete element method；heat transfer；fixed beds