Purpose

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.

Design/methodology/approach

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).

Findings

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.

Practical implications

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

Originality/value

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.

中文翻译：

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热流效应下柔性印刷电路板传热变形分析

目的

本研究的目的是通过流体结构相互作用研究在热和流动效应下柔性印刷电路板 (FPCB) 的热传递和变形。本研究模拟电子设备在 FPCB 运行期间在力对流下产生热量时的电子冷却过程。

设计/方法/方法

在仿真中研究了带有附加球栅阵列 (BGA) 封装的 FPCB 上的热和流动效应。研究了雷诺数 ( Re )、连接的 BGA 封装数量、提供给 BGA 封装的功率和 FPCB 尺寸的影响。本研究中的响应是 FPCB 的挠度/长度 ( δ/L ) 和 Nusselt 数 ( Nu )。

发现

重要的是要同时考虑热效应和流动效应，以了解在工作条件下附有 BGA 的 FPCB 的特性。的经验相关性方程重新，普朗特数（镨），δ/ L和女已经建立，在该最高的效果是重，其次是镨和δ/ L。的δ/ L和 N你¯ 被发现受大多数参数因素的显着影响。

实际影响

本研究提供了对 FPCB 组装过程控制的更好理解。

原创性/价值

本研究为热耦合建模提供了基本指南和参考，以解决 FPCB 设计中的可靠性问题。它还增加了对 FPCB 和 BGA 接头问题的理解，以实现微电子设计中的高可靠性。