软质弹体与身管瞬态相互作用机理及匹配设计理论研究

In order to solve the technical problem of how the match design between the soft bullet and barrel to affect the firing accuracy for high quality sniper rifle or sporting rifle, the project will develop the theoretical models and explore the transient multi-field interaction mechanism between soft bullet and barrel. The stress-strain relationship of the lead material used at bullet’s core will be studied under high strain rate. The simulation models of the squeezing process of bullet to rifle will be built and the affecting relationship of match parameters between the soft bullet and barrel to the engraving resistance and bullet’s indentation in barrel will be investigated by numerical and experimental method. A transient multi-field simulation model will be built which considers the gas flow, the deflection and vibration of barrel, the elastic and plastic deformation of bullet, high velocity movement of bullet and contacting or impacting of bullet to the inner barrel. The affecting relationship of match parameters between the soft bullet and barrel to the vibration of barrel and the posture of bullet at muzzle will be investigated by simulation and experiment, and the main parameters will be obtained for the match design of the bullet and rifle. The project will figured out the matching sensitivity factors and the error transition calculating method, and propose the design criterion of matching design for the bullet/rifle. A new design methodology for the bullet/rifle will built up by the above simulation models combined with design of experiment、response surface modeling and robust design. The results of the project will provide the theoretical foundation for the system design of sniper rifle or the sporting rifle. They also have the important value to greatly improve the fire accuracy of our country’s sniper rifle or sporting rifle and develop the design theory for the high quality barrel weapon.

针对高品质狙击枪、比赛枪的软质弹体与身管匹配影响射击精度这一共性技术问题，开展软质弹体与身管瞬态多场相互作用机理、计算模型等基础研究。研究弹芯用铅材料在高应变条件下的应力-应变关系，建立弹体挤进过程计算模型，结合试验研究软质弹体与身管挤进匹配参数对挤进阻力、弹体刻痕状态等影响规律。考虑铅等软质材料动态性能变化及发射过程多场耦合作用，建立含火药气体流动、身管热弹变形及振动、弹体弹塑性变形、高速运动及与内膛接触碰撞的软质弹体/身管瞬态相互作用计算模型，通过试验和数值分析研究匹配参数对身管振动、弹体出膛口姿态影响规律，获得匹配主控参数。建立匹配敏感因子和误差传递计算方法，提出弹体/身管匹配设计准则，结合均匀试验设计、代理模型和稳健性设计，构建一套弹枪匹配设计新方法。研究成果将为狙击枪、比赛枪系统设计提供科学依据，对提高我国狙击枪和比赛枪射击精度、丰富高精度身管武器设计理论具有重要意义

针对高品质狙击枪、比赛枪的软质弹体与身管匹配影响射击精度这一共性技术问题，开展软质弹体与身管瞬态多场相互作用机理、计算模型等基础研究。使用分离式霍普金森杆试验获得了弹芯用铅在高应变条件下的应力-应变关系，构建了铅材料的动态本构方程，为计算高精度狙击步枪、比赛枪挤进和弹/枪相互作用提供了基本材料模型。建立了软质弹体挤进理论计算模型和数值仿真计算模型，试验获得了狙击步枪弹挤进阻力，验证了模型的正确性；研究获得了挤进过程阻力变化特性及参数影响规律。建立了发射过程考虑火药燃烧、软质弹体/身管热固瞬态多场耦合相互作用计算模型，通过试验验证了模型正确性，研究发现软质弹体与身管相互作用过程中软质弹丸头部位移曲线呈螺旋状，初始运动阶段受挤进过程的影响，弹头头部摆动较为混乱，随后摆动位移逐步增大，并逐渐遵循螺旋线规律进行摆动，射弹散布主要是由弹头在膛内摆动产生的起始扰动引起；研究获得了身管和枪弹主控参数，包括坡膛锥度、自由行程、膛线缠度、膛线条数、膛线宽度和深度、枪管长度、枪管外径、弹头圆柱部长度、弹重误差、弹头质量偏心、装药量、火药力与药室容积等对弹体膛内运动影响规律，揭示了软质弹体与身管瞬态相互作用与匹配机理。建立了一种基于“内弹道、弹体/身管相互作用、外弹道”参数传递的射击精度预测模型，解决了枪械射击精度难于预测问题；建立了一种单发发射过程误差传递计算模型，可以通过误差分析快速预估狙击枪、比赛枪射弹散布。基于软质弹体/身管耦合相互作用计算模型和稳健设计思想，采用弹体膛内最大摆动角的均值与极差为目标函数，构建了一套弹枪匹配稳健设计方法，应用实例表明该方法是可行的；建立了一套高精度狙击步枪与比赛枪弹/枪匹配设计规程；研究成果将为狙击枪、比赛枪系统设计提供科学依据，对提高我国狙击枪和比赛枪射击精度、丰富高精度身管武器设计理论具有重要意义。