为对电磁发射矩形炮膛用一体化C形电枢结构进行优化设计,基于仿真计算研究了电枢装配接触压力分布不均匀特性。通过模拟电枢轨道的装配过程,利用ABAQUS有限元分析软件,计算了初始静态情况下不同结构电枢与轨道的接触压力分布。仿真验证了电枢装配接触压力的不均匀分布,同时根据压强分布云图,提出并定义了4个不均匀系数,分别表征接触压力横向、纵向、总体、局部分布的不均匀程度。这些不均匀系数的取值范围都介于0~1之间,其值越大,对应分布的不均匀程度就越小,即分布越均匀。基于进一步计算,获得了各不均匀系数随基本电枢结构参数的变化规律:各不均匀系数受电枢过盈量的影响较小,随电枢尾翼长度增加变小,随电枢肩部厚度增加变大;而随翼尖厚度变化呈现不同变化趋势。
To improve the design of C-shaped monolithic armatures used in rectangular-bore railguns, we studied the non-uniformity of contact pressure distribution in armature assembly based on numerical simulation. The simulation was conducted using the finite element analysis software ABAQUS to calculate the pressure distribution on the contact surface between assembled armature and rail in static state. The simulation verifies the non-uniformity of the contact pressure distribution. On the basis of the contour pattern of pressure distribution, we proposed four coefficients to represent the non-uniformity of transvers-direction, launch-directi0n, overall, and local contact pressure distributions, respectively. All of these coefficients range between 0-1, and the higher their values are, the more non-uniform the corresponding distribu- tions are. Based on further calculation, we also obtained the relation between these coefficients and some basic structural parameters of armature: the four coefficients are barely influenced by the interference of armature, decrease with increas- hag the tail length, increase with increasing the bulk depth, but vary in different pattern with increasing the rear radial depth.