机枪遥控武器站锰铜基阻尼合金缓冲器非线性有限元分析及试验

The Nonlinear Finite Element Analysis and Experiment of Mn-Cu Damping Alloy Buffer for Remote Control Weapon Station

机枪遥控武器站缓冲器存在能量吸收率低、二次冲击、刚度过大等现象,导致枪口振动加剧,影响射击精度.针对上述问题,本文基于锰铜基阻尼合金开展新型缓冲器的设计研究.对锰铜基阻尼合金广义分数阶Maxwell本构模型进行有限元实现,开展锰铜基阻尼合金悬臂梁振动特性实验验证子程序正确性.采用遗传优化算法设计了8片对合组合和24片复合组合两种新型阻尼合金碟簧缓冲器,进行非线性瞬态有限元分析发现24片复合组合碟簧缓冲器效果较好,相对原矩形圆柱弹簧缓冲器的振动加速度有效值可降低66.42%.最后通过缓冲器静压试验和落锤试验验证了仿真分析结果.静压试验表明3 kN时24片复合碟簧静态能量吸收率可达37.1%,落锤试验表明其平均动态能量吸收率为63.64%,是原矩形圆柱弹簧缓冲器的1.51倍,最大位移为2.69 mm,相对原矩形圆柱弹簧缓冲器降低30%.

There are some problems in the buffer of machine gun remote control weapon station, such as low energy absorption rate, secondary impact and excessive stiffness, which lead to the aggravation of muzzle vibration and affect shooting accuracy. In order to solve the above problems, a new type of buffer was designed and studied based on Mn-Cu damping alloy. The generalized fractional Maxwell constitutive model of Mn-Cu damping alloy was realized in finite element software, and vibration characteristics tests of Mn-Cu damping alloy cantilever beam were carried out to verify the subroutine. Two types of disc spring buffers were designed using genetic optimization algorithm. One is made of 8 pieces of disc springs, which are placed opposite each other. The other is made of 24 pieces of disc springs that set three congruent pieces as one group and the groups are placed opposite each other. After the nonlinear transient finite element analysis for two kinds of new buffer, it is found that the vibration absorption effect of the 24-pieces disc spring buffer is better than the other one. Its vibration acceleration RMS values can be reduced by 66.42% when compared with the original rectangular spring buffer.The static pressure test shows that the static energy absorption rate of 24 pieces disc spring can reach 37.1% at 3 kN. The drop weight test shows that its average dynamic energy absorption is 63.64%, which is 1.51 times that of the original rectangular spring buffer. And its maximum recoil displacement is 2.69 mm, which has decreased30% compared with that of the original rectangular spring buffer.