COMBINED MICROWAVE AND CONVECTIVE DRYING OF A POROUS MATERIAL

被引:113
作者
TURNER, IW
JOLLY, PG
机构
[1] Energy Laboratory, Department of Mechanical Engineering, University of Queensland, St. Lucia
关键词
MODELING; WATER PUMPING; POWER DISTRIBUTION; VARYING DIELECTRIC PROPERTIES; MOISTURE LEVELING; RESONANCE; UNCHARACTERISTIC DRYING KINETICS;
D O I
10.1080/07373939108916749
中图分类号
TQ [化学工业];
学科分类号
0817 ;
摘要
A model is formulated to describe the drying of a slab of porous material in a combined microwave and convective environment. The model describes the evolution of temperature, pressure, moisture and power distributions that occur during the drying process. The microwave internal heat source is calculated from electromagnetic theory with varying dielectric properties. The inclusion of pressure in the model allows the physical phenomena of "water pumping", often observed in microwave drying systems, to be accounted for. The influence of sample size on the drying kinetics is examined and found to be an important parameter during the drying process. In particular the effect of resonance on the moisture and temperature profiles and the need for careful consideration of surface mass transfer coefficients are investigated. Simulation results are presented for the combined microwave and convective drying of a homogeneous, isotropic porous material.
引用
收藏
页码:1209 / 1269
页数:61
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