某结构的多轴随机振动实验研究

Multiaxial Random Vibration Research of a Typical Structure

通过对某结构开展多轴随机振动试验研究,初步探讨了典型线性结构在多轴随机振动试验中的动力响应特点。首先对多轴振动试验系统、试验条件、控制方式等进行了介绍;然后通过有限元仿真了解结构的自振频率、振型和响应情况;重点对结构的多轴随机振动试验结果进行研究,具体分析了结构各测点加速度响应谱的共振峰特点;最后将多轴试验结果与单轴试验结果进行对比,并理论上解释了多轴随机振动响应不同于单轴振动的原因。研究结果表明:多轴振动试验能同时激发结构在不同方向的模态,使动力响应表现出比单轴振动更为丰富的共振峰,因此对经受多轴振动环境的产品开展多轴振动试验很有必要。

Dynamic response characteristics of a typical linear structure in the multiaxial random vibration tests were experimentally investigated. First, the multiaxial vibration test system, experimental condition and control fashion are briefly introduced. Then, the structure resonance frequency, vibration mode and dynamic responses were acquired through finite element simulation. The results of multiaxial random vibration test were research emphases, especially the resonance peak characteristics of response spectrum were detailedly analyzed. Finally, the results of multiaxial random vibration tests were compared with those of singleaxial random vibration tests. And the inducement of the difference between them was theoretically explained. Results show that structural modes in different directions can be excited at the same time in multiaxial vibration test, which causes the response spectra with more resonance peaks. So, the multiaxial random vibration test is essential for manufacture of those products that may suffer multiaxial vibration environment.