Heat transfer from a horizontal wafer-based disk of multichip modules

Convective heat transfer characteristics above a horizontal wafer-based dis k heated with 15 simulated chips in unobstructed ambient air have been expe rimentally investigated under both stationary and rotating disk conditions. Relevant parameters influencing heat transfer performance studied are the Grashof number and rotational Reynolds number. Their effects on heat transf er characteristics in such configurations of stationary and rotational heat ed disks are successively explored. The heat transfer enhancement of rotati on on the heated disk has been investigated; the effect of natural convecti on on the heat transfer behavior of the heated rotating disk has also been explored. Three heat transfer regimes dominated by purely forced convection of rotation, mixed convection and purely natural convection are classified over a wide range of a system parameter, Gr/Re-r(2). Also, in the natural convection aspect, two new empirical correlations of average Nusselt number in terms of temperature difference and Grashof number are proposed. In the mixed convection aspect, another two explicit composite correlations of av erage Nusselt number for mixed convection caused by the mutual effect of di sk rotation and buoyancy are also proposed. Satisfactory comparisons of the predictions evaluated by the proposed correlations with the present experi mental data are achieved. (C) 1998 Elsevier Science Ltd. All rights reserve d.