ON TEMPERATURE DISTRIBUTION AND HEAT TRANSFER CHARACTERISTICS OF A PHASE CHANGE MATERIAL IN AN ANNULUS

Giuma M. Fellah; Yamen Abdelwhab

doi:10.66411/jer.v10i10.172

Authors

Giuma M. Fellah Department of Mechanical and Industrial Engineering Faculty of Engineering, Al-Fateh University Tripoli-Libya Author
Yamen Abdelwhab Department of Mechanical and Industrial Engineering Faculty of Engineering, Al-Fateh University Tripoli-Libya Author

DOI:

https://doi.org/10.66411/jer.v10i10.172

Keywords:

Phase Change Material, Enthalpy, Finite volume, Saturation temperature, Refrigerants

Abstract

This paper presents a numerical model of a two–dimensional axi-symmetrical transient controlled heat conduction of Phase Change Material (PCM). The system consists of a copper tube surrounded by a coaxial cylinder which forms an annular gap around the tube. The annular is filled with PCM while the two-phase fluid undergoes heat exchange through a tube wall. The finite volume approach for numerical modeling of phase change problem is employed. The essential feature of this approach is that the evolution of latent heat is accounted for by the definition of total enthalpy (H), while the two-phase fluid flows is modeled via a single energy equation with empirical correlation for the heat transfer coefficient. A parametric study is carried out to find out influence of different kinds of refrigerants, refrigerant saturation temperature, discharging time, and refrigerant mass flow on the temperature distribution inside the PCM, and the amount of heat released by PCM. Three refrigerants with different properties are selected for the present study; those are, carbon dioxide (R744), Freon 134a (R134a) and Freon 407C (R407C). The results show that the refrigerant R744 is characterized with the best heat transfer characteristics, and the lowest solidification time of PCM

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