Dynamic model and experimental study of an air–water heat pump for residential use

• Published in: International journal of refrigeration Vol. 36; no. 3; pp. 674 - 688
• Main Authors: Koury, R.N.N., Faria, R.N., Nunes, R.O., Ismail, K.A.R., Machado, L.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2013; Elsevier
• Subjects: Applied sciences; Devices using thermal energy; Domestic; eau chaude sanitaire; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Experimentation; expérience; Heat exchangers (included heat transformers, condensers, cooling towers); Heat pump; Heat pumps; Hot water; Modelling; modélisation; pompe á chaleur; Refrigerants; Refrigerating engineering; Refrigerating engineering. Cryogenics. Food conservation; résidentielle; expérience; Heat pump; Domestic; eau chaude sanitaire; Experimentation; résidentielle; Modelling; modélisation; Hot water; pompe á chaleur; Water; Refrigeration installation; Temperature; Vapor compression; Modeling; Pressure; Energy savings; Capillary tube; Energy balance; Mass flow rate; Energy conservation; Heat exchanger; Distribution; Instability; Hot water production; Dynamic model; Mathematical model; Refrigerant fluid
• ISSN: 0140-7007; 1879-2081
• DOI: 10.1016/j.ijrefrig.2012.11.006

This paper presents a study of the dynamic behavior of a vapor compression heat pump for residential water heating. The mathematical models for heat exchangers are formulated by using mass, momentum, and energy conservation equations, while capillary tube model is based on the equations of conservation of momentum. The model is formulated from the manufacturer experimental data and the energy conservation balance. The contribution of this study to the field of dynamic modeling appears on the convergence of models of heat exchangers, this being accomplished with a variable error in spatial and time minimizing the instabilities in the calculation. The coupling among the four components allows the determination of the spatial and temporal profiles of temperatures, pressures and mass flow rates, as well as the refrigerant distribution in the heat exchangers during the water heating process. The validation of the model is done by comparison with the experimental results. ► It was made a model in transient regime for a heat pump air-water for residential use. ► It was designed a heat pump air-water prototype for residential use in order to validate the proposed model. ► Reasonably good agreement between the experimental data and numerical simulations was obtained. ► The proposed model proved to be an excellent tool for the study and analysis of this type of equipment.