为进一步提高电磁轨道炮模型试验的有效性,基于电磁轨道炮物理场模化方法,通过理论分析和数值仿真对电磁排斥力作用下的原型与模型轨道动态响应相似性问题进行了研究。结果显示:如果电磁轨道炮的模化方法,在原型和模型中采用相同材料,并且要同时实现磁场和温度场的匹配,则必将导致应力场的不匹配和轨道动态响应的不相似;在匹配速度的近似模化方法下,原型轨道和模型轨道的临界速度相同,但动态响应属于非线性关系,而且随着弹丸速度和滑动距离的增加,挠度曲线相关系数变小、相似性变差,而振幅比值与几何相似常数近似相等。
In order to further improve the effectiveness of the tests on sub-scale electromagnetic railgun, theoretical analysis and numerical simulations are carried out to assess the similarity performance of rail dynamics under the condition of the fields scaling method of the EM railgun launcher. The results show that: the stress field and rail dynamics can not be matched as long as the scaling method is desirous to use the same material in two scales and to match the magnetic and temperature field as well; at velocity matching approximate field scaling condition, the rails of sub-scale and full-scale launchers have the same critical velocity, but the rail dynamics are the non-linear relations, and the correlation coefficient is getting smaller with armature moving, the amplitude approximately scales as the geometric scaling factor.