DOI: 10.1615/ICHMT.2008.CHT
ISBN Print: 978-1-56700-253-9
ISSN: 2578-5486
THE OPTIMAL SPACING BETWEEN PARALLEL HEAT GENERATING BOARDS COOLED BY TURBULENT FORCED CONVECTION
ABSTRACT
The main objective of this study is to maximize the total rate of heat transfer from the finite space occupied by the package to the air that flows through the package. Turbulent forced convection heat transfer in parallel heat generating boards in fixed volume of electronic package is investigated numerically. The boards are assumed to be equidistant and constant pressure head is maintained for the electronic package for varying spacing of heat-generating boards. Board surfaces with uniform temperature and uniform heat flux are considered. The optimal boar-to-board spacing that maximizes the total heat transfer rate removed by the turbulent flow of air is obtained by complete numerical simulation of the turbulent flow of air and temperature fields in each channel of fixed volume electronic package.
The result of the optimization procedure shows that an optimal spacing exists for the turbulent flow but unlike in laminar flow as indicated in literature [Bejan and Sciubba 1992 and Mereu, Sciubba and Bejan 1993] it is not independent from the type of thermal boundary condition (uniform temperature or uniform heat flux). The optimal spacing for uniform heat flux condition is approximately 25% smaller than when the board surfaces are isothermal. The optimal spacing is
found to be dopt ★ L4/5(αμ)1/10/(δP)1/10 . The maximum heat transfer rate that corresponds to optimal board-to-board spacing is also obtained.