Transient convention adjacent to discrete components in the presence of a weak opposing pressure field

This study deals with the transient flow of air in a channel that has discrete heated components. The channel is subjected to a weak pressure field that opposes the buoyancy induced flow. This simulates electronic packages that are cooled by natural convection, but are sometimes subjected to a pressure field that opposes the flow. This pressure field could result from a blower intended to provide forced convection cooling in another section of the system, and could also arise due to stratification within the box. Both the transient and the final steady state are investigated. The computational technique selected to solve the governing equations is an Eulerian-Langarngian finite difference scheme. A two dimensional numerical model is used. The model is verified by comparing the results with a known aiding mixed convection flow. The overall effect of an opposing pressure gradient is found to be very significant in changing the nature of the flow field and in suppressing the heat transfer from the heated components. For some circumstances of relatively large pressure fields, significant temperature overshoots are observed during the transient.