ANALYSIS OF PCM STORAGE USING NON - CIRCULAR GEOMETRY

Abstract

The melting characteristic of a PCM in a vertical cylinder using non-circular heating channels has been investigated numerically. Extensive numerical analyses were carried out for two different channels of square and triangular cross-section using enthalpy method and numerical grid generation technique. Transient results were obtained for melted fraction, temperature variation and solid-liquid interface position. All the results were calculated by taking different values of Stefan number. Since, the conduction is the only dominant mode of heat transfer throughout the process of melting, the melting is found to be almost uniform and symmetric. The grid sizes and time step size have negligible effect on the melted fraction of PCM. As the value of aspect ratio, ratio of cylinder radius to length of square or triangular section of the channel, increases, melting rate decreases and hence the time required for melting increases. Square channel requires less time to melt completely as compared to the time required for the triangular channel configuration. The results when compared with experimental results available for horizontal cylinder found to be in excellent agreement for initial short period of time. ill