posted on 1991-01-01, 00:00authored byJay S. Nigen, Cristina H. Amon, Carnegie Mellon University.Engineering Design Research Center.
Abstract: "Grooved-channel geometries are formed when electronic components are directly mounted to a substrate. Some grooved-channel geometries have been found to excite and sustain the normally damped instabilities present in Poiseuille flows at lower Reynolds numbers than indicated by linear stability analysis. The resulting self-sustained oscillatory flows improve mixing and thereby enhance convective heat dissipation. Numerical simulations of the flow field and heat transfer characteristics of oscillatory and non-oscillatory flows for five grooved- channel and one suspended block geometry are presented. The extent of heat transfer enhancement is gauged through direct comparison to results corresponding to the steady-flow regime.Local heat transfer coefficients are determined and used to calculate the temperature distribution within a surface-mounted package. Furthermore, the importance of using locally defined heat transfer coefficients instead of spatially-averaged coefficients for thermal design and analysis is discussed."