Hierarchical implementation of hybrid heat promoters fixated on operational conditions to accelerate the melting phenomenon of a triplex tube heat exchanger

Abstract

Heat storage is regarded as a chief necessity in multiple applications, especially in buildings and air conditioning equipment. The ubiquitous low efficiency of such systems is the prime reason which prompts phase change materials (PCM) to receive considerable attention. In the present study, a numerical 2D domain of a concentric and an eccentric triplex tube heat exchanger (TTHX) has been performed by ANSYS 15.0 to cast light on thermal performance in existence of porous media while varying operational conditions are applied simultaneously. As results are validated against an experimental study, the findings show substantial reduction of up to 81% and 25% in melting time due to porous media and eccentric arrangement, respectively. Despite substantial betterment in melting behavior by implementing the above-mentioned scenarios individually, merging these two reverses the upward trend by an average of 24.75% compared to concentric porous scenario. Regarding operational condition, unlike prior studies, it is shown that each case reacted differently with increasing temperature and flow rate, especially the latter induces more dichotomous patterns. Rationalization of this reveals the major role of porous media in this contrasting behavior as porous-media-included cases hold less significant share of improvement upon surging HTF temperature while with HTF flow rate jumping from 3 to 5 lit/min, 20% more efficiency is detected for concentric porous-embedded scenario compared to plain case.