Experimental investigation on phase change behavior of nanocomposite phase change material filled inside the shell and tube heat exchanger

Abstract In this paper, melting and solidification characteristics of composite PCM filled inside the shell and tube heat exchanger were investigated experimentally. ZnO nanoparticles (NPs) were synthesized using the sol–gel method. Myristic acid (MA) considered as the pure PCM and ZnO NPs serving as the supporting material. The morphology and crystal structure of ZnO particles were analyzed using Field Emission Scanning Electron Microscopy (FESEM) and x-ray Diffraction (XRD) techniques. ZnO nanoparticles at concentrations of 0.1, 0.3, and 0.5 wt% were individually dispersed in myristic acid to evaluate the heat transfer characteristics of nanocomposite phase change materials (NCPCMs) through phase change processes. Differential Scanning Calorimetry (DSC) analyses were used to assess the phase change behavior of PCM and nanocomposite PCMs in liquid and solid states. The phase change characteristics of the Myristic acid and nanocomposite PCMs were probed with regard to heat exchanger studies. The results show significant time savings, with a 68.04% reduction in complete melting time and a 42.73% reduction in solidification time when using 0.5 wt% ZnO NPs at a mass flow rate of 5 l min ⁻¹ . Furthermore, incorporating ZnO NPs at concentrations of 0.1, 0.3, and 0.5 wt% enhanced the thermal conductivity of the NCPCMs by 36.41%, 62.96%, and 82.71%, respectively, compared to pure MA.