Calculation of Forced-Air Cooling of Electronic Modules With a Two-Fluid Model of Turbulence
The flow and heat transfer characteristics in a forced-air cooled electronic device are calculated with a two-fluid model of turbulence. The fluids are defined as turbulent and nonturbulent, and precludes the need for low-Reynolds number model in the near-wall regions. Transport equations are solved for the zone-averaged variables of each fluid. Empirical relations, established in prior work, are used to express interchange of mass, momentum, and energy at the interface. Gradient-diffusion flux is considered an intrafluid source of turbulence. Several cases are considered showing effects of Reynolds number and heat-dissipation density on the flow and thermal fields. A critical comparison is made between the results based on the application of this model and the conventional k-ε model. Such results include velocity vectors and temperature distribution. In addition, the two-fluid model predicts spatial distribution of the intermittency factor, which provides a measure of the extent of turbulence and mixing in the electronic system.