考虑组分相互作用的飞艇蒙皮材料力学模型

平流层空间空气稀薄,昼夜温差变化剧烈,巡航状态的平流层飞艇需要承受较大的循环压差载荷。蒙皮作为平流层飞艇的主要承力结构,其材料力学性能直接影响着飞艇的使用性。针对蒙皮材料层压结构特点,构建其细观结构模型。通过研究拉伸过程中纤维纱束与基体和膜层的相互作用,指出承力方向纤维纱束的变形过程分为弯曲状态逐步拉直和产生伸长形变两个阶段。建立了蒙皮材料拉伸过程的非线性力学模型;并通过与准静态拉伸试验获得的材料应力-应变曲线进行对比分析,校验了模型的准确性并分析了模型参数的改变对材料力学性能的影响,为平流层飞艇蒙皮材料结构优化设计提供依据。

Mechanical model of airship envelop considering component interaction

In the stratosphere space, extremely thin air and highly changed temperature make the stratosphere airship need to undertake high differential pressure load periodically. Envelope, as the main load-bearing structure of the stratospheric airship, its mechanical properties directly affect the use of the airship. According to film-fabric laminate structure characteristics of the envelope materials, a micromechanics model is created. By studying the interaction between the fiber yarn, the matrix and the film, the deformation process of fiber yarn in load-bearing direction is divided into two stages, the bending state gradually straightening and elongation deformation generating. In this paper, a nonlinear mechanical model is established for the tensile process of the envelope materials. Next, quasi-static tests are conducted to obtain the stress-strain curve. The theoretical calculation results are compared to the test results and the accuracy of the model is checked. Moreover, the influences of the model parameters on the mechanical properties of the materials are analyzed. The proposed model provides basis for structural optimization design of the stratospheric airship envelope materials.