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The flexible printed circuit board (FPCB) can be an alternative to the rigid printed circuit board because of its excellent flexibility, twistability, and light weight. Using FPCB to construct personal computer (PC) motherboard is still rare. Therefore, the present study aims to investigate the fluid‐structure interaction (FSI) behaviors of the newly proposed FPCB motherboard under fan‐flow condition in the PC casings.

The deflection and stress induced, which are usually ignored in the traditional rigid motherboard, are the main concern in the current FPCB motherboard studies. Only a few studies have been conducted on the effect of inlet locations, effect of inlet sizes, effect of multi‐inlets, and effect of a two‐fan system. These numerical analyses are performed using the fluid flow solver FLUENT and the structural solver ABAQUS; they are real‐time online coupled by Mesh‐based Parallel Code Coupling Interface (MpCCI).

A smaller inlet size can cause higher deflection and stress fluctuations, but the fluctuations can be reduced by incorporating the multi‐inlets design. In addition, the inlet locations and two‐fan system can prominently affect the magnitudes of the deflection and stress induced.

The current study provides better understanding and allows designers to be aware of the FSI phenomenon when dealing with the FPCB motherboard. Although the present study primarily focuses on the motherboard, the findings could also contribute valuable information for other FPCB applications.

The present study extends the FSI investigation from the previous novel approach of FPCB motherboard, and uniquely explores the behaviors of the FPCB motherboard inside different PC casings.

The purpose of this study is to investigate heat transfer and deformation of flexible printed circuit board (FPCB) under thermal and flow effects by using fluid structure interaction. This study simulate the electronic cooling process when electronic devices are generating heat during operation at FPCB under force convection.

The thermal and flow effects on FPCB with attached ball grid array (BGA) packages have been investigated in the simulation. Effects of Reynolds number (Re), number of BGA packages attached, power supplied to the BGA packages and size of FPCB were studied. The responses in the present study are the deflection/length of FPCB (δ/L) and Nusselt number (Nu).

It is important to consider both thermal and flow effects at the same time for understanding the characteristic of FPCB attached with BGA under operating condition. Empirical correlation equations of Re, Prandtl number (Pr), δ/L and Nu have been established, in which the highest effect is of Re, followed by Pr and δ/L. The δ/L and Nu¯ were found to be significantly affected by most of the parametric factors.

This study provides a better understanding of the process control in FPCB assembly.

This study provides fundamental guidelines and references for the thermal coupling modelling to address reliability issues in FPCB design. It also increases the understanding of FPCB and BGA joint issues to achieve high reliability in microelectronic design.

This study aims to investigate the interaction of independent variables [Reynolds number (Re), thermal power and the number of ball grid array (BGA) packages] and the relation of the variables with the responses [Nusselt number ((Nu) ¯ ), deflection/FPCB’s length (d/L) and von Mises stress]. The airflow and thermal effects were considered for optimizing the Re of various numbers of BGA packages with thermal power attached on flexible printed circuit board (FPCB) for optimum cooling performance with least deflection and stress by using the response surface method (RSM).

Flow and thermal effects on FPCB with heat source generated in the BGA packages have been examined in the simulation. The interactive relationship between factors (i.e. Re, thermal power and number of BGA packages) and responses (i.e. deflection over FPCB length ratio, stress and average Nusselt number) were analysed using analysis of variance. RSM was used to optimize the Re for the different number of BGA packages attached to the FPCB.

It is important to understand the behaviour of FPCB when exposed to both flow and thermal effects simultaneously under the operating conditions. Maximum d/L and von Misses stress were significantly affected by all parametric factors whilst (Nu)¯ is significantly affected by Re and thermal power. Optimized Re for 1–3 BGA packages with maximum thermal power applied has been identified as 21,364, 23,858 and 29,367, respectively.

This analysis offers a better interpretation of the parameter control in FPCB with optimized Re for the use of force convection electronic cooling. Optimal Re could be used as a reference in the thermal management aspect in designing the BGA package.

This research presents the parameters’ effects on the reliability and heat transfer in FPCB design. It also presents a method to optimize Re for the different number of BGA packages attached to increase the reliability in FPCB’s design.

The aim of this study is to investigate the effects of offset angle in wave soldering by using thermal fluid structure interaction modeling with experimental validation.

The authors used a thermal coupling approach that adopted mesh-based parallel code coupling interface between finite volume-and finite element-based software (ABAQUS). A 3D single pin-through-hole (PTH) connector with five offset angles (0 to 20°) on a printed circuit board (PCB) was built and meshed by using computational fluid dynamics preprocessing software called GAMBIT. An implicit volume of fluid technique with a second-order upwind scheme was also applied to track the flow front of solder material (Sn63Pb37) when passing through the solder pot during wave soldering. The structural solver and ABAQUS analyzed the temperature distribution, displacement and von Mises stress of the PTH connector. The predicted results were validated by the experimental solder profile.

The simulation revealed that the PTH offset angle had a significant effect on the filling of molten solder through the PCB. The 0° angle yielded the best filling profile, filling time, lowest displacement and thermal stress. The simulation result was similar to the experimental result.

This study provides a better understanding of the process control in wave soldering for PCB assembly.

This study provides fundamental guidelines and references for the thermal coupling method to address reliability issues during wave soldering. It also enhances understanding of capillary flow and PTH joint issues to achieve high reliability in PCB assembly industries.