Three-Dimensional Thermal Analysis of Heat Sinks With Circular Cooling Micro-Channels

The pressure drop and heat transfer characteristics of heat sinks with circular micro-channels are investigated using the continuum model consisting of the conventional Navier-Stokes equations and the conventional energy equation. Developing flow (both hydrodynamically and thermally) is assumed in the fluid region and three-dimensional conjugate heat transfer is assumed in the solid region. Thermal results based on this approach are shown to be in good agreement with existing experimental data. Numerical results obtained for heat sinks with various geometries indicate that the heat absorbed by the fluid per unit length is high at the inlet and decreases steadily in the flow direction. As a result, the bulk temperature increases at a higher rate near the inlet. The geometry of the heat sink is shown to have a significant effect on the overall thermal resistance.