Flow modeling in air-cooled electronic enclosures

Computational fluid dynamics (CFD) has indisputably become a very useful tool in the early design phase of electronics systems. Its success, however, does not guarantee accurate predictions in all situations. Therefore, this paper focuses on typical, but complex, flow features where the predictive capability of CFD is still rather poor. Examples are given for enclosures with forced convection cooling. Different aspects of system level modeling are analyzed: fan modeling and induced swirling flow, pressure loads and friction forces induced by screens and flow aspects in between printed circuit boards (PCBs) or more specifically around in line positioned electronic components. All numerical results are thereby compared to experimental data.