Effect of package spacing on convective heat transfer from thermal sources mounted on a horizontal surface

• Published in: Applied thermal engineering 2018-03, Vol.132, p.676-685
• Main Authors: Ali, R.K., Refaey, H.A., Salem, M.R.
• Format: Article
• Language: English
• Subjects: Aerodynamics; CAD; Circuit boards; Circuit design; Computational fluid dynamics; Computer aided design; Convective; Convective heat transfer; Electronic module; Fluid dynamics; Fluid flow; Heat transfer; Heat transfer coefficients; Mathematical analysis; Numerical and experimental; Nusselt number; Printed circuit boards; Reduction; Reynolds number; Three dimensional analysis; Wind tunnels
• ISSN: 1359-4311; 1873-5606
• DOI: 10.1016/j.applthermaleng.2018.01.006

•Three-dimensional analysis of an inline module composed of two thermal sources.•Applicable range of air velocity (2464⩽ReL⩽16,430), package spacing ratio (1⩽s/L⩽3).•The gap effect on upstream thermal source temperature is vanished at s/L = 3.•Increasing package spacing more than 3 has almost no additional enhancement on the downstream thermal source.•Nusselt number correlations for the module were presented. This work introduces a three-dimensional analysis of an inline module composed of two thermal sources using ANSYS-FLUENT Computational Fluid Dynamics (CFD) package. The effect of package spacing ratio (1 ≤ S ≤ 3) on the heat transfer coefficient of the upstream (UTS) and downstream (DTS) thermal sources within Reynolds number range of 2464⩽ReL⩽16,430 are considered. The predictions are compared with the experiments performed on air wind tunnel with two thermal sources mounted on its horizontal surface within Reynolds number range of 4848⩽ReL⩽13,635. The numerical results are compared and validated with the experimental results and a good agreement is obtained. Compared to a single thermal source (STS), it is observed that the reduction in the average Nusselt number of the UTS and DTS is 26.3% and 35.6%, respectively, at S = 1. This reduction decreases to 4.9% and 12.6%, respectively, at S = 3. Finally, the present study aims to extend the printed circuit boards designers with average Nusselt number correlations for the UTS and DTS as a function of Reynolds number and package spacing within 2464⩽ReL⩽16,430 and (1 ≤ S ≤ 3).