Latent heat energy storage using nanomaterials as a heat sink for the prevention of thermal runaway: A study in conjugate heat dissipation

Abstract

Phase change material (PCM) based heat sinks are the passive cooling technologies that achieve required thermal management. PCM increases the energy storage capacity, and adding nanomaterial to the PCM improves the heat sink capacity. However, there are very few studies on the effect of heat load on thermal performance in this field. This research focuses on the experimental investigation of the thermal characteristics of Nano-PCM-based heat sinks with varying base roughness and load. To enhance the heat transfer characteristics of paraffin PCM, two distinctive nanoparticles, i.e., graphene and Silver Titanium Dioxide (Ag-TiO2), are used. Two different heat sinks containing one of the nanoparticles mixed PCM were tested. However, one more heat sink containing only PCM was also used in the study. Scanning electron microscope analysis, thermogravimetric analysis, differential scanning calorimetry, and energy dispersive X-ray analysis were performed, and the performance was measured at various heat loads (25 W, 35 W, and 45 W), and different roughness configurations (R1, R2, and R3) with PCM and Nano-PCM. The study's findings indicate that the R3 configuration containing graphene-PCM performs better than the others. It had a longer charging time (heating), a shorter discharging time (cooling), and a more constant temperature during discharging. Comparing the discharging cycles of AgTiO2-PCM, graphene-PCM reveals a minor difference. The cooling rate depends on the heat load and a heat load of 45 W results in a faster cooling rate.