Numerical Simulation of Heat and Moisture Transfer in Deep Air Buried

Abstract

Analyzed characteristics of heat and moisture transfer and condensation. Deep duct heat and moisture transfer model is established. The function of heat and mass transfer during condensation was added to the corresponding control equation as a source term which took advantage of the user-defined-functions of FLUENT software. The three-dimensional simulation on transient conditions was carried out considering coupled heat and moisture transfer of air in the tunnel. Simulated results with different inlet parameters given show that air temperature difference between inlet and outlet of the tunnel, quantity of condensation and heat flux are all increased as the air inlet temperature rises, while the air temperature difference decreases and the quantity of condensation and the heat flux increase as both inlet relative humidity and velocity increase. Lay the foundation for prediction of temperature and humidity during ventilation, calculation of heat and moisture load, and utilization of geothermal energy in underground constructions.