Experimental analysis of natural wax as phase change material by thermal cycling test using thermoelectric system

Abstract

The stability of the type of Phase Change Material (PCM) during operation are important factors to know before PCM applied. The purpose of this study is to analyze the characteristics and thermal stability of PCM using the thermal cycle testing. The development of thermal cycle test method to test the thermal stability of PCM has been carried out in this study by using thermoelectric as a heating and cooling media with the number of cycles, namely 500, 1000, 3000 and 5000. The PCM used in this study is consisted of 3 types that derived from natural waxes, namely palm wax, soy wax and paraffin wax. All the natural wax have chemical compositions (C and O) and morphological form are lump layer. The Differential Scanning Calorimetry (DSC) results show that the lowest melting and freezing points are owned by soy wax at 43.92 °C and 38.49 °C, respectively. Thermoelectric as a thermal cycle test device and the addition of the test module to 4 modules can increase the test efficiency. Thermoelectric characterization for 1 h produce 24, 13 and 45 cycles for palm wax, soy wax and paraffin wax, respectively. This thermal cycle tester was capable of testing up to 5000 cycles in each module. Degradation of the thermal properties occured for each wax after 5000 cycles. The highest reduction value of ΔH was observed for soy wax that reaced 60% reduction in ΔH freezing. Overall, based on these degradations of PCM after treated a number of cycles, they can provide data on the time when the PCM should be replaced with new material.