Abo Bibliothek: Guest

ISSN Online: 2377-424X

ISBN Print: 0-89116-130-9

International Heat Transfer Conference 6
August, 7-11, 1978, Toronto, Canada

HEAT AND MASS TRANSFER IN POROUS MEDIA WITH PHASE CHANGE

Get access (open in a dialog) DOI: 10.1615/IHTC6.2340
pages 1-12

Abstrakt

The paper aims at a clear presentation of the important features characterizing combined heat and mass transfer in a porous medium and specifically in soils. A description of the soil characteristics leads to an idealized model and the assumption of capillary dominated conditions is used to illustrate the way in which soils hold liquid water for equilibrium in the absence of gravity or with gravity. The basic equations describing the transport of liquid water under isothermal conditions and the transport of vapor and energy in the presence of temperature gradients are developed.
Because of the importance of the thermal conductivity for the heat transfer process, a new quasi-steady method has been developed suitable for accurate laboratory measurements of the thermal conductivity of soils for a wide range of parameters. Considering the time required for an individual test, moisture migration does not affect the results in contrast to steady state methods. Results for "Moon Valley Silt" indicate a strong dependence of the thermal conductivity on moisture content and a minor dependence on temperature.