A theoretical model for effective thermal conductivity (ETC) of particulate beds under compression

被引：1
作者：
Galit Weidenfeld
Yeshayahu Weiss
Haim Kalman
机构：
[1] Ben-Gurion University of the Negev,Laboratory for Conveying and Handling of Particulate Solids, Department of Mechanical Engineering
来源：
Granular Matter | 2004年 / 6卷
关键词：
Effective thermal conductivity; Particulate beds; Compression; Heat transfer;
D O I：
暂无
中图分类号：
学科分类号：
摘要：
Thermal conductivity of particulate beds is an important property for many industrial handling processes as well as for storage of particulate materials. This paper presents a new theoretical model that is based on heat transfer between particles in three modes: heat conduction through contact area, heat conduction through voids and radiation through voids. The model is further adjusted in order to obtain effective thermal conductivity of a particulate bed by using empirical augmentation factors for the heat transfer coefficient of each one of the heat transfer mechanisms. Comparison of the results predicted by the semi-empirical model to our experimental results show good agreement. The theoretical model was investigated to examine the effect of various parameters (such as: particle elasticity and surface roughness, particle and gas thermal conductivity and particle diameter), on the effective thermal conductivity of various particulate beds. Our results show the significant effect of the contact area (that is a clear function of the compression load) between particles on the effective thermal conductivity.
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页码：121 / 129
页数：8
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