用无梯度仿生技术对叠层复合材料方板开孔形状优化

Shape optimization of interior cutouts in square laminated composite panels using non-gradient biomimetic technique

为了改善叠层复合材料方板孔周应力分布,采用一种无梯度仿生技术——固定网格渐进优化方法,建立了等限制Tsai-Hill准则——即使孔周的限制Tsai-Hill值更加均匀,来求解切孔形状优化问题。用各向同性材料方板在二轴拉力荷载下单孔形状优化的例子验证了方法的正确性。研究了按照[±45°/0°/90°]对称搁置的碳纤维/环氧树脂材料准各向同性叠层复合材料方板受单拉和拉剪荷载的例子。优化后的孔形在Tsai-Hill强度值的均匀度上比正方形开孔有了显著的改善,计算结果比传统的渐进优化方法更精确和更光滑。

The stress distribution around interior cutouts in square laminated composite panels was optimized using a non-gradient biomimetic fixed grid evolutionary structural optimization method to achieve the most uniform Tsai-Hill factor, which provides an effective means for shape optimization of cutouts in laminated composite panels. The method was first validated using benchmarking problems of isotropic material plates loaded in biaxial tension. The optimal shape of cutouts in quasi-isotropic symmetrical [±45°/0°/90°] carbon fibre laminated composite panels was sought for biaxial and biaxial-shear stress loads. The uniformity of the Tsai-Hill factor for optimized interior cutouts was much better than for the non-optimized square interior cutouts. The resulting boundaries are much smoother and more accurate than those designed by the conventional evolutionary structural optimization method.