A numerical investigation of melting phase change process via the enthalpy porosity approach: Application to hydrated salts

作者：Younsi Zohir; Naji Hassane^*

来源：International Communications in Heat and Mass Transfer, 2017, 86: 12-24.

DOI：10.1016/j.icheatmasstransfer.2017.05.012

• Phase change material
• Natural convection
• Numerical simulation
• Finite volume method
• Enthalpy-porosity formulation
• Melting
• Fusion

The convection dominated melting of hydrated salts (PCM 27) is investigated numerically using a pressure based finite volume method (FVM) with an enthalpy porosity technique, which allows a fixed-grid solution of the coupled momentum and energy equations, and trace the solid-liquid interface without resorting to other equations or transformations. This investigation addresses effects of Rayleigh number, the aspect ratio and Prandtl number on the effectiveness of melting process and solid-liquid interface. In addition, the average Nusselt number is set to complete the parametric study conducted. Through the results achieved, the enthalpy porosity has been found to converge rapidly while producing accurate results for both the position and morphology of the melt front at different times. The results are presented in terms of temperature profiles, streamlines, isotherms, moving interface position, liquid fraction and average Nusselt number. From this survey, it appears that our numerical findings support the experimental observations. These results indicated that, in terms of efficiency of the melting process, the best configuration of the rectangular container is the cavity having an aspect ratio of 0.19 (H = 21 cm; W = 4 cm). Therewith, it is found that the time required to melt the material is proportional to the Rayleigh number and the convection heat transfer. Finally, this study demonstrates the feasibility for simulating macro-encapsulated hydrated salts via the enthalpy-porosity-based approach.

• 出版日期2017-8