Flow Induced Deflection and Stress on Flexible Printed Circuit Board in Fan-Cooled Electronic Systems: FSI Approach

Flexible printed circuit boards (FPCBs) are going to replace rigid boards (PCBs) in numerous electronic devices due to their reduced thickness and ability to bend and adapt to various shapes. Deflection and stress are key factors affecting the reliability of FPCBs. In this paper, the fluid flow solver FLUENT and structural solver ABAQUS, are used to study the deflection and stress induced by axial flow fan on FPCBs, in the fan sucking mode. The flow is assumed to be 3-D, laminar, compressible, and steady. The effect of air flow rate on the force acting on the components mounted on the FPCB is analyzed. In the structural simulation using ABAQUS, the deflection and stress are observed for nine cases of different mounting options of the FPCB, at a fixed air flow rate. The proper selections of air flow rate and mounting option are found to be crucial in minimizing the flow induced deflection and stress in FPCBs.