纤维增强复合材料螺旋弹簧刚度预测模型

建立了一种通用形式的复合材料螺旋弹簧刚度预测模型，提出一种无需限定网格和节点的复合材料螺旋弹簧有限元建模方法.基于复合材料层合板理论，推导了复合材料层合板等效剪切模量，并据此建立了纤维增强复合材料螺旋弹簧刚度预测模型，该模型能够适用于任意铺层角度的纤维分布.为了解决在有限元建模过程中复合材料螺旋弹簧单元方向设置的难题，提出建立复合材料弹簧有限元模型的新方法，可直接对铺层进行设计，避免了划分网格时单元坐标系与簧丝螺旋线方向难以协调的问题.刚度预测模型计算结果与文献实验结果的对比表明，所建立的预测模型具有更好的计算精度.针对复合材料类型和纤维铺层角度的不同组合形式，利用所建立的有限元分析模型和刚度预测模型进行了对比分析，结果表明两者之间的计算误差较小，有效性较好. 

A Stiffness Prediction Model for Fiber Reinforced Plastic Coil Spring

A general form of stiffness prediction model was built for fiber reinforced plastic coil spring, and a finite element modeling method was presented for finite element without considering the mesh or node number. Based on the theory of composite laminates, the equivalent shear modulus of laminates was derived and used to establish a stiffness prediction model for fiber reinforced plastic coil spring, being applicable for arbitrary ply angle. In order to avoid the difficulties in coordinating the direction between the element coordinate systems and spring helix, a novel finite element modeling method was presented to design the laminating directly without considering the mesh. The comparison between stiffness prediction model and the experiment result in reference shows that the accuracy of the prediction model is better than the prediction model in the reference. Considering the various combination of composite material and ply angle, a comparative analysis between the prediction model and the finite element model was conducted. The results show that the error between the prediction results and the FEA results are small, which indicate the effectiveness of the proposed model.