碳纤维复合材料壳体轴压稳定性分析与试验验证

Stability analysis and test verification of carbon fiber composite case under axial compression

针对碳纤维复合材料壳体轴压稳定性问题,提出了理论推导、数值模拟和试验验证相结合工程计算方法,获得了铺层相关参数对轴压稳定性的影响规律。基于层合板理论,计算了碳纤维复合材料壳体的等效弹性常数;以?150 mm碳纤维复合材料圆筒为研究对象,通过壳体破坏性轴压试验,验证了理论计算和有限元数值模拟的正确性;计算了碳纤维缠绕角及增加0°铺层对复合材料弹性常数的影响规律。研究结果表明,通过引入修正系数k=0.4,理论计算结果与实际轴压破坏载荷较为接近;通过增加0°铺层数,能够大幅度地提高壳体刚度,且对刚度提升的贡献远大于所引起的重量增加。复合材料刚度是决定壳体临界轴压载荷的关键因素,固体发动机设计过程中增加材料刚度可有效提升其轴压稳定性。

Aiming at the axial compressive stability of carbon fiber composite case,an engineering calculation method combining theoretical derivation,numerical simulation and test verification was proposed,and the influence of the ply parameters on the axial compressive stability was obtained.Based on the theory of laminated plates,the equivalent elastic constant of the carbon fiber compos?ite case was calculated.The correctness of the theoretical calculation and finite element numerical simulation was verified by means of the destructive axial compressive test of the case for ?150 mm carbon fiber composite cylinder.The influence of carbon fiber winding angle and the addition of 0°ply on the elastic constant of composites was calculated.The results show that the theoretical calculation results are close to the actual axial compressive failure load by introducing the correction coefficient k=0.4;the case stiffness can be greatly improved with increasing the number of 0°plies,and the contribution to the stiffness increase is far greater caused by weight gain.The stiffness of the composite material is the key factor determining the critical load of the case under axial compression.Increas?ing the material stiffness during the design of the solid rocket motor can effectively improve its axial stability.