Paper Title
Experimental Investigation on Heating and Cooling Cycle of NEPCM based Composite Plate Fin Heat Sinks for Transient Electronic Cooling

Abstract
In the present work, the thermal performances of passively cooled NEPCM plate finned heat sinks were experimentally investigated. Nano enhanced phase change material (NEPCM) composite heat sinks are made of thermal conductivity enhanced myristic acid filled in the plate finned aluminum enclosure. The effect of NEPCM volume fraction, TCE volume fraction on the critical operating time of the electronic devices was discussed. The time taken by the un-finned heat sinks filled with NEPCM was taken as the baseline to have the best comparison among the heat sink configurations. The maximum enhancement ratio of 1.87 was achieved for the cross finned heat sinks having 9 % volume fraction of TCE is same as that of the Pin finned heat sinks tested in the reference article. Decrement in the volume fraction of the NEPCM in both the parallel and cross finned heat sinks by 50% had reduced the enhancement operating time of the heat sinks by 60% in comparison to the fully NEPCM heat sinks. The optimum fin thickness to completely melt the NEPCM was found to lie around 1.5 mm for all the heat inputs. The thermal resistance of the heat sinks started to decrease from 2 K/W to 0.6 K/W while increase in the air flow rate in the heat sinks was observed. The modified heat sink showed cooling time decrement of 50% compared with the un-finned NEPCM filled heat sinks, which obviously reduced the fan power energy consumption. The energy consumption of the fan had reduced by 63% for modified heat sinks for one hour of operating period even thought at the maximum operating conditions. The effect of the modified Stefan number on the pre-melting, melting and post melting periods for all the heart sinks configurations is briefly discussed. Keywords- NEPCM, TCE, Thermal Resistance.