Masashi Kuramae

On the Vapour Transfer Rate in Porous Media under a Temperature Gradient

This paper deals with the problem of the vapour transfer rate in porous media such as granular bed under a temperature gradient. The microscopic temperature and temperature gradient distribution in porous media were calculated by numerical relaxation method for two regular packed models. These results revealed that the value of ξ which defined as the ratio of the temperature gradient in air filled void to that of the overall porous media was 1.5–2.0 for usual packed bed. The mass transfer experiments under a constant temperature gradient were achieved In this experiments, granular beds of glass sphere particles that contained sublimate substance, for example, naphthalene were used as the sample and the quantities of this substance transfered as vapour state in a designated period were measured by quantitative analysis of gas chromatography. As the results, it was found that the experimentally obtained vapour transfer rate was generally larger than that of the calculated value by a past simple mass transfer model and these gave support to our theory.