Modeling of a Condenser in Dynamic Operation Using Comsol Multiphysics Software

This paper is about modelling in dynamic operation the heat exchanger system using as condenser in one dimension characterized by two coaxial tubes with ribbed inner tube by using the equations of mass, momentum and energy conservation. The Comsol PDE interface is used to simulate the monophasic and biphasic flows of refrigerant. Heat transfer in water and inner wall of the condenser are modeled with two Heat Transfer Interfaces (solid, fluid) in Comsol software.

The model has been validated by comparing the numerical and experimental results obtained with the direct expansion geothermal heat pump. The analysis of the comparative results shows that the obtained model adequately fits the experimental data with an average deviation of less than 5%. Therefore, it proves that it's a good model which can be used for simulation purposes. This developed numerical model was used to simulate the superheating, condensing and subcooling phases in the condenser. Vapor quality, pressure, enthalpy of the refrigerant and water temperature are also simulated.