Fractal Pattern Effects on Natural Convection Heat Transfer and Flow Characteristics

Thermal management is necessary to dissipate heat from semiconductors while keeping system efficiency high. There is a clear need for compact, effective, reliable, high-capacity, and quiet, passive cooling systems in the power electronics industry. A novel Smith-Volterra-Cantor (SVC) set fractal heat-sink is introduced and numerically investigated for natural convection. The SVC fractal pattern increases the heat transfer area and interrupts the thermal and aerodynamic boundary layers. The heat-sink mass and size are reduced with the SVC fractal design compared to the classical ones that make compact passive cooling system design feasible. The thermal performance of the fractal heat-sink is detailed, considering the fin scale and surface heat flux. The analysis indicates mass normalized fin effectiveness is improved, and the temperature is more uniformly distributed for fractal design. These results are applicable for the development of compact power-electronics passive thermal management design for telecommunication and aviation applications with reduced parasitic powers, noise, and vibration.