薄壁复合材料圆筒稳定性模拟分析研究

Simulation Analysis and Research on Thin Walled Composite Cylinder Stability

纤维增强树脂基复合材料具有高比强度、高比刚度、质量轻、抗疲劳性强等优点,复合材料圆筒应用于旋转机械,结构为多层缠绕,包括角度层和环向层。对于转速较高的旋转机械,为提高复合材料圆柱壳体的承载能力,圆柱壳成型后需要对筒体施加一定的预应力,如果施加预应力过大可能导致圆柱壳的屈曲失稳,影响整体性能。本文采用有限元方法对复合材料圆筒的稳定性问题进行了分析研究,建立有限元壳体模型,通过特征值法计算失稳临界压力,并分析铺层厚度、铺层角度、铺层顺序对复合材料圆筒稳定性的影响。计算结果表明,环向缠绕层的厚度占比越大,复合材料圆筒的失稳临界压力越大;在一定范围内,改变角度层的缠绕角度对复合材料圆筒的失稳临界压力没有影响;改变铺层顺序对复合材料圆筒临界压力影响较大。

The fiber reinforced resin matrix composites material has the advantages of high specific strength,high specific stiffness,light weight,and strong fatigue resistance.Composite cylinder is used in rotating machinery,and the structure is multi-layer winding,including angle layer and hoop layer.In order to improve the bearing capacity of composite cylindrical shell,a prestress should be applied to the cylindrical shell after forming.Greater prestress may lead to bucking instability of the cylindrical shell and affect the performance.In this paper,composite cylinder stability is analyzed by finite element method,the finite element shell model is established,the critical pressure is calculated by eigenvalue method,and the influence of layer thickness,layer angle and layer sequence on the stability of composite cylinder is analyzed.The results show that the critical pressure of instability increase with the ratio of hoop layer thickness.In certain range,changing the winging angle of the angle layer has no effect on the critical pressure of composite cylinder.The critical pressure of composite cylinder is greatly affected by changing layering order.