Influence of dry and wet atmospheres on the unsteady thermal behaviour of materials in a cavity

摘要

An experimental study has been made of the influence of different convective atmospheres on the thermal behaviour of materials in a rectangular cavity. The atmospheres can be dry air, humid air, or superheated steam. Two kinds of materials are studied: porous and nonporous. The comparisons show a benefit in using humid atmospheres to reach the saturation temperature in a minimum of time. Afterwards the behaviours tend to those obtained with dry air. The presence of humidity within the material modifies the heating kinetics as well under dry air as under steam. By normalising the central temperature, predictive models have been proposed, giving the central temperature history for each material under the different kinds of convective atmospheres.