Modeling and Analysis of a Direct Geothermal Heat Pump (DX): Part II-Modeling of Water-Refrigerant Exchanger

J. Fannou[1], C. Rouseau[1], L. Lamarche[1], S. Kajl[1]
[1]École de Technologie Supérieure, Montréal, Canada

In this section, we simulate the heat exchanger system in one dimension characterized by two coaxial tubes with ribbed inner tube using the equations of conservation of mass, conservation of momentum and energy. The COMSOL PDE interface is used to simulate the monophasic and biphasic flow of refrigerant R22 (Chlorodifluoromethane). Heat transfer in waterand inner wall of the exchanger are modeled with two Heat Transfer interfaces (solid, fluid). The developed numerical model was used to simulate the phases of superheating, condensing and subcooling in the condenser. Vapor quality, pressure, enthalpy of the refrigerant and the water temperature are also simulated. To validate this numerical model a comparison between numerical and experimental results was performed.