Using a thermal simulation model to interpret test data [air cooling of circuit boards]

The concurrent utilization of testing and simulation models is advocated as a means of improving the thermal characterization process. One such model based upon a combination of integral energy and momentum balances and local thermal networks is described. The general process of data interpretation using a simulation model is outlined as a series of guidelines. The process is illustrated through a series of tests involving air-cooling of boards with regular and irregular component layouts. Specific sensitivities tested included component powering, component height, and arrangement heterogeneity. The treatments of the convective heat transfer coefficient and the flow split among component flow channels were found to be the most important sensitivities in these tests. Using simulation models is considered to reduce uncertainties in estimating adiabatic heat transfer correlations. Recommendations and guidance are provided for an innovative approach to thermal characterization using existing technology