V型皱褶芯材夹层结构强迫对流传热与热应力分析

V型皱褶芯材夹层结构与强迫对流冷却相结合,可应用于高超声速飞行器或大功率电子器件承载和散热的多功能设计。文章采用数值仿真方法对强迫对流条件下V型皱褶芯材夹层结构的换热及其产生的热应力进行研究,获得了相应的速度场、温度场及结构热应力分布。结果表明:强迫对流条件下,V型皱褶芯材夹层结构的换热性能明显提高,同时导致较大的压力损失。流体速度场随着几何构型的改变而发生周期性的变化,在结构偏折处波峰一侧流速达到最大,对流换热得到增强;沿着冷却液流动方向,结构与冷却液的温度逐渐升高,并伴随着周期性的波动;皱褶芯材夹层结构的整体换热能力随着入口流速的增大而增强。热流输入侧的面板热应力和变形均较大,结构皱褶部位存在应力集中。

Heat transfer and thermal stress analyses of V-pattern folded core sandwich structures subjected to forced convection

The combination of the V-pattern folded cores and the forced convection may apply to the multifunctional design the simultaneous load bearing and the heat dissipation for hypersonic vehicles or high-power electronic devices. The heat transfer and thermal stress characteristics of a V-pattern folded core sandwich panel subjected to the forced convection are investigated numerically to obtain the velocity field, the temperature field, and the structural thermal stress distribution. It is shown that the heat transfer performance of the V-pattern folded panels is evidently improved under the forced convection, however, an elevated pressure drop is also observed. The coolant velocity varies periodically with the geometrical construction and reaches the maximum value close to the peak position of the buckling, where the heat convection is therefore reinforced. The temperature increases along the flow direction and sees a periodic fluctuation. The overall heat transfer performance is refined with the increase of the inlet velocity. The thermal stress as well as the deformation are comparatively large in the face sheet near the heat source and the stress concentration is found at the folding positions.