能量耗散法在航天电子设备结构设计中的应用

Application of Energy Dissipation in Aerospace Electronic Equipment's Structure Design

航天电子设备抗振动能力验证一般包括有限元分析及实物振动试验。在分析中若发现印制电路板某些元器件加速度响应过大,一般采取局部加强法提高局部刚度减小其响应,但对有些结构此方法效果并不理想。因此本文从能量耗散的角度出发,提出一种新的减小响应的方法:随机振动输入能量一定,若有意消弱某些次要结构的刚度来消耗振动能量,则分配在电路板上的能量会相应减小,即在减轻结构重量的同时达到减小元器件响应的目的。并选取典型单机,通过有限元分析比较局部加强法和能量耗散法的效果,结果表明:局部加强法使单机加速度响应增加0.9%,能量耗散法减小29%,效果明显。

The vibration environmental validation of aerospace electric equipment includes FEM analysis in the stage of design and vibration test in the phase of experiment. The partial enhancement is usually used to increase local stiffness and decrease acceleration response which is beyond the demand in the analysis. But sometimes,this measure does not work well. In this paper,a new method to decrease acceleration response is used from energy dissipation point of view. AS the whole energy of vibration is certain,if the subordinate structure expends more energy via diminishable stiffness,the energy on PCB will be reduced with less weight and acceleration response. A representative structure＇s acceleration response was analyzed with both partial enhancement method and energy dissipation method. The result shows that acceleration response increases 0. 9% with the former and decreases 29% with the latter.