圆柱筒式空投气囊缓冲模拟

Simulation of Cushion Characteristic of Cylindrical Airdrop Airbag

目的研究某空投缓冲系统圆柱筒式气囊的缓冲过程,得出缓冲特性曲线,并校核装备冲击过载。方法基于有限元理论,利用Ansys中的显示动力学分析软件LS-DYNA建立气囊缓冲系统的有限元模型,采用粒子法,对气囊缓冲过程进行数值模拟,并与传统气囊仿真所使用的控制体积法进行对比。结果经模拟得出空投着陆缓冲过程中气囊排气口打开时间为63.4 ms,缓冲过程中的最大过载为13.3g,获得了缓冲高度、货台加速度等特性的变化规律。将气囊缓冲特性与使用传统的控制体积法仿真的结果进行了对比,排气口打开时间误差为10.7%,最大过载误差为8.6%。结论 2种方法的结果对比一致性较好,验证了粒子法进行缓冲气囊模拟的可行性,同时使用圆柱筒式气囊缓冲的最大过载满足装备空投对过载不超过20g的要求。

The work aims to study the cushioning process of the cylindrical airbag in some airdrop cushioning system to obtain the cushioning curve and check the impact overload of the equipment. Based on the finite element theory, the finite element model of the airbag cushioning system was established with the explicit dynamic analysis software LS-DYNA in Ansys. The numerical simulation of airbag cushioning process was conducted in the particle method and compared with the control volume method used in the traditional airbag simulation. Based on the simulation, the opening time of the airbag exhaust port in the airdrop landing cushioning process was 63.4 ms, the maximum overload in the cushioning process was 13.3g, and the change rule of such characteristics as cushioning height and loading acceleration were obtained. By comparing the airbag cushioning characteristics with the results from the simulation carried out in the traditional control volume method, the opening time error of exhaust port was 10.7% and the maximum overload error was about 8.3%. Based on the result comparison of these two methods, they have a good consistency. The feasibility of cushion airbag simulation in the particle method is verified and the maximum overload of the cylindrical airbag used for cushioning meets the requirement that the overload does not exceed 20 g for equipment airdrop.