Heat Transfer Performance of a Phase Change Microcapsule Fluid

Polyalphaolefins (PAOs) are widely implemented for electronics cooling. However, they have a low thermal conductivity. Adding nanoparticles to a PAO can significantly improve the thermal properties of the coolant. In this paper, the thermal performance of phase change materials (PCM) fluids with reduced supercooling in the phase transition was studied in a microchannel heat sink, and compared with that of the pure PAO. A test loop was designed and fabricated to test the synthesized PCM fluids. The PCM fluid with uncoated PCM particles has a 36% higher heat transfer coefficient than the pure PAO. The heat transfer coefficient of a silver coated PCM coated was also higher than of the pure PAO but lower than of the uncoated PCM. The thermal resistance of the uncoated PCM fluid was about 20% lower that of the PAO fluid at the same pumping power, despite the PCM fluid’s higher viscosity. Pumping tests run for several hours showed no effect on particle accumulation or settling within the heat transfer loop.