The product had to be cooled by natural convection airflow for reasons of noise and cost. The prototype CAD model of the product was slimmer than the older model which would limit airflow through the system.
The primary orientation of the product during use was vertical, which was best for airflow, but the product also needed to meet the thermal performance requirements in the worst-case orientation, when the product was horizontal.
The initial CFD analysis showed that as designed, the top and bottom enclosure vents severely limited airflow. The CFD model predicted that this would cause several electronic components to operate above their temperature limits.
Dust accumulation in the vents over time might reduce system airflow and cause overheating.