Main Article Content
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.
Fannou J.-L, Rousseau C, Lamarche et L, Stanislaw K. Experimental analysis of a direct expansion geothermal heat pump in heating mode. Energy and Buildings. 2014;75:290-300, 6//.
Michopoulos et A, Kyriakis N. A new energy analysis tool for ground source heat pump systems. Energy and Buildings. 2009;41:937-941.
Rousseau C, Fannou J.-L. C, Lamarche L, Ouzzane et M, Kajl S. Modeling and experimental validation of a transient direct expansion geothermal heat exchanger. Geothermics. 2015;57:95-103. 9//.
Fannou J-L, Rousseau C, Lamarche et L, Kajl S. Modeling and analyse of a direct expansion geothermal heat pump (DX) : part 2 Modeling of Water-Refrigerant Heat Exchanger dans COMSOL CONFERENCE, Boston, USA; 2012.
Ndiaye D. Étude numuréique et expérimentale de la performance en régime transitoire de pompes à chaleur eau-air en cyclage. PhD, École polytechnique de Montréal, École polytechnique de Montréal, Université du Québec, Montréal, Canada; 2007.
COSTIC. Les pompes à chaleur géothermiques très basses énergies, Guide de l'installateur; 2009.
Garimella et S, Christensen RN. Heat Transfer and pressure drop characteristics of spirally fluted annuli: Part II—Heat Transfer. Journal of Heat Transfer. 1995;117:61-68.
Rousseau PG, van Eldik et M, Greyvenstein GP. Detailed simulation of fluted tube water heating condensers. International Journal of Refrigeration. 2003;26:232-239.
Ndiaye D. Transient model of a refrigerant-to-water helically coiled tube-in-tube heat exchanger with corrugated inner tube. Applied Thermal Engineering. 2017;112:413-423.
Fannou J.-LC, Lamarche L, Semassou Guy C, Stanislaw et K, Vianou A. Cooling mode experimental analysis of a direct expansion geothermal heat pump with a control depending on the discharge pressure. Applied Thermal Engineering. 2019;160:113955.
Garimella et S, Christensen RN. Heat transfer and pressure drop characteristics of spirally fluted annuli: part i—hydrodynamics. Journal of Heat Transfer. 1995;117:54-60.
Koyama S, Miyara A, Takamatsu et H, Fujii T. Condensation heat transfer of binary refrigerant mixtures of R22 and R114 inside a horizontal tube with internal spiral grooves. International Journal of Refrigeration. 1990;13:256-263.
Ndiaye et D, Bernier M. Transient model of a geothermal heat pump in cycling conditions – Part A: The model. International Journal of Refrigeration. 2012;35:2110-2123.