Comparison of heat transfer enhancement between open and closed cell porous metal structures for solid-liquid phase change

PurposeThe purpose of this study is to analyze heat transfer for solid-liquid phase change in two inclined cavities assisted with open cell and closed cell porous structures for enhancement of heat transfer and compare them. Design/methodology/approachThe heat transfer analysis is done numerically. The set of conservation equations for mass, momentum and energy for phase change material (PCM) and conduction heat transfer equation for metal frame are solved. Furthermore, temperature and solid-liquid fraction distributions for a cavity filled only with PCM are also obtained for comparison. The porosity is 0.9 for both porous structures. Rayleigh number and inclination angle change from 1 to 10(8), and from -90 degrees to 90 degrees, respectively. FindingsThe present study reveals that the use of closed cell structures not only can make phase change faster than open cell structure (except for Ra = 10(8) and = 90 degrees) but also provide more stable process. The use of a closed cell porous structure in a cavity with PCM can reduce melting period up to 55% more than a cavity with an open cell porous structure. The rate of this additional enhancement depends on Rayleigh number and inclination angle. Originality/valueTo the best of the authors' knowledge, this is the first time that the comparison between closed cell and open cell porous structures for heat transfer enhancement in a solid/liquid phase change process is reported. Authors believe that the present study will lead more attentions on the use of closed cell porous structures.