模块化Marx发生器机芯的力学环境适应性分析及优化设计

为研究Marx发生器机芯在公路运输条件下的力学环境适应性,基于随机振动理论和有限元分析方法对Marx机芯进行了仿真分析和随机振动试验。首先,建立了八级模块化Marx机芯的有限元动力学仿真模型,模拟确定了机芯的应力集中点;然后,通过振动台运输振动摸底试验修正了有限元模型,对机芯结构进行了优化设计,使Marx机芯整体一阶频率由15.4 Hz提高到19.7 Hz,降低了整机垂向的动力学响应,提高了机芯的力学环境适应性。试验结果表明,Marx发生器结构设计需要重点考虑其在垂直方向的可靠性;振动过程中,机芯整体连接稳定,振动应力集中于机芯与U型支撑杆连接处、支撑杆与支撑板连接的角片处,以及开关连接件处,是结构设计的薄弱环节。

Adaptability analysis and optimization design of modular Marx generator in mechanical environment

To study the adaptability of the modularized Marx generator in mechanical environment, simulation and vibration experiment of the generator are conducted based on the random vibration theory and finite element analysis method. Firstly, the finite element simulation model of an 8-stage Marx generator is established, and the stress concentration positions are identified. Secondly, the finite element model is corrected according to the initial results of shaking table test. Then an optimization scheme is proposed to modify the Marx generator. As a result, the first-order frequency of the Marx generator is increased from 15.4 Hz to 19.7 Hz. It is helpful to reduce the dynamic response in vertical direction and enhance the mechanical environment adaptability. Results show that more attention should be paid to the reliability in vertical direction when a Marx generator is being designed. The connection of the generator is stable in the vibration experiment, and the stresses mainly concentrate on the corner pieces between the generator and the U-shape support plates, the connections between U-shape support plates and side support plates, and the switch junctions, which are the weak points in design.