Composite pin-fin heat sink for effective hotspot reduction

Abstract

This current work aims to decrease temperature nonuniformity in a microprocessor. The proposed composite pin-fin heat sink design is analyzed computationally, and its functioning is compared with the conventional heat sink design. According to the heat rate, the composite heat sink is divided into two sections: the hotspot and the background section. Aluminum, copper, and graphene are chosen for the background and hotspot sections. Both noncomposite and composite heat sinks are designed with similar geometrical dimensions. DI water is used as the working fluid. They are studied for heterogeneous hotspot heat flux varying from 200 to 600 kW/m² by keeping constant background heat flux as 100 kW/m² with the inlet mass flow rate of 0.05 kg/s. Further simulations are performed for various Reynolds numbers (Re = 150, 225, 300) with a constant background and hotspot heat flux of 100 and 600 kW/m², respectively, for different inlet temperatures of 15°C, 20°C, and 25°C. The simulations are also carried out for other working fluids, such as TiO₂ and Fe₂O₃ based nanofluids with the constant volume concentration of 0.65% and 3%, respectively in the DI water, at the constant background and hotspot heat flux of 100 and 600 kW/m², respectively. The results are shown for all the above studies planned. The results suggest that composite heat sinks with graphene as a composite material and Fe₂O₃ based nanofluid yields higher heat dissipation.