Characterization of Phase Change Material-Based Heat Sinks for Cyclic Heat Loads
Rajesh Akula, C. Balaji
Abstract
Literature suggests to use a fin volume fraction of 8% in the Phase Change Material (PCM) based heat sinks to get the maximum thermal control for constant heat loads. However, the same volume fraction may not be the optimum for cyclic loads. In the present numerical investigation, the thermal characteristics of a PCM based heat sinks having different volume fraction of fins (0, 8, 15.6, and 25.7%) when subject to cyclic heat loads of square, triangle, and sawtooth profiles having time periods vary from 100 to 400 s are studied in detail. All the heat sinks and fins are made of Aluminum, and the PCMs considered are Eicosane and RT-52. The present numerical results report that the heat sink with an 8% volume fraction of fins is the best in handling cyclic heat loads of time periods more than 100 s with the maximum enhancement ratios of 6.1 for Eicosane and 4.1 for RT-52. Whereas, for heat loads with 100 s time period, the heat sink with 15.6% volume fraction of fins turns out to be the best, regardless of the heat load profile, with the maximum enhancement ratios of 5.74 and 3.9 for Eicosane and RT-52, respectively.