Thermal and humid environment and moisture condensation characteristics of cold surfaces

Abstract

In this study, an actual condensation model of radiant cooling system was built to investigate the condensation characteristics of cold surfaces and the thermal and humid environment near the surfaces. Dimensionless analysis was undertaken combined with multiple linear regression to explore how condensation rate would vary with governing factors, such as moisture content difference, heat flux, and temperature difference between the cold surfaces and the nearby air. The calculation formula of dew quantity is presented with good accuracy and moisture content difference was proven to be the most influential factor of dew quantity among the governing factors. This paper is presented to provide a reference for future optimization of cold radiation system and to establish boundary conditions for CFD simulation.

Keywords

Radiant cooling Radiant panel Moisture condensation Dew quantity Boundary layer

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