Heat transfer enhancement of electronic devices by using flexible printed circuit boards

Abstract

In this paper, heat transfer in electronic equipment was studied numerically and experimentally, by investing in the flexible printed circuit board and changing the board’s orientation, which is the substrate of the electronic equipment from a vertical to a horizontal position. ANSYS Fluent software has been used to solve the continuity, momentum, and energy equations with the three-dimensional, unsteady, laminar and incompressible flow. In this study, the oscillatory motion equation was used as a boundary condition to represent the motion of the flexible board. In the experimental aspect of this study, a simulation of an ASUS motherboard (X399-A) with dimensions (30 x 25) cm and a Core i9 CPU with a fully working power of 130W was used to study the enhancement of heat transfer in the electronic devices by test rig specially made for this study. The results show that the flexible board’s enhancement in the heat transfer was (7%) vertically and (7.6%) horizontally compared with the rigid board for the same working conditions. The horizontal position is better than the vertical of the two types of rigid and flexible board, with improved heat transfer rates of (2.7%) and (3%); correlation Equations of the Nusselt number from experimental results are presented.