This paper presents a comparative study on\nheat transfer in a packed column. Two methods of heating\nare considered: microwave and convective. Transient onedimensional\nmathematical models were proposed to\ndescribe the both alternatives. To account for significant\ndifferences in the temperatures between the gas and solid\nphase a heterogeneous model was applied in the modelling.\nThe numerical simulations were carried out for different\noperating conditions. The effects of the gas inlet temperature\nand the microwave power, the bed porosity, the\npenetration depth of microwaves and the gas velocity were\nexamined. The simulation results were compared on the\nbasis of the time profiles of the average bed temperature\nand the outlet gas temperature. The same electric power\nutilized in the microwave heated packed column and the\nconvective heated packed column was established as the\nkey criterion for the comparisons. The compared profiles\nintersect indicating the time ranges in which the one or the\nother solution provides higher temperature of the bed. It\nwas displayed that the microwave heated packed column\nshould be preferred when longer heating times are required.\nIn turn, the convective heated packed column is the better\nchoice when shorter heating times are needed.
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