基于虚拟体的弹炮刚柔耦合动力学优化设计研究

为了研究火炮系统结构参数对弹丸膛内运动和炮口扰动的影响,通过引入虚拟体,提出了一种充分反映弹炮间相互作用的火炮动力学建模方法,推导了含虚拟体项的自行火炮刚柔耦合动力学方程;同时,以某型履带式自行火炮为例,引入多目标优化算法,建立了以弹丸和炮口初始扰动为目标函数的火炮系统多目标优化设计模型,获得了在相同射击条件下试验测试数据和仿真计算结果的对比曲线,以及结构参数的优化结果。分析表明,采用该方法建立的模型能较真实地反映火炮系统的动态响应特性和弹丸的膛内运动规律,且在考虑弹丸与柔性身管接触碰撞的前提下实现了弹丸和火炮运动的多目标优化设计,可以为自行火炮的发射动力学研究提供一定参考。     

多管火箭总传递方程自动推导和动力学可视化仿真方法研究

多管火箭系统总传递方程的自动推导和动力学快速计算是多管火箭系统动力学设计的关键。针对某新型多管火箭,建立多管火箭多体系统发射动力学模型及其拓扑结构,根据符号约定和各元件传递方程,建立了某多管火箭系统总传递方程自动推导方法,提高了多管火箭多体系统建模效率和程式化水平。建立了多管火箭系统动力学可视化仿真系统,实现了新型多管火箭动力学快速可视化仿真,并得到了试验验证。为新型多管火箭动力学设计提供了理论基础。     

基于柔性多体动力学理论的舰船机械设备隔振系统建模

将柔性多体动力学理论应用于非线性隔振系统建模过程中,建立了线性弹性元件及非线性弹性元件的力学模型,利用该力学模型和单柔性体的动力学微分方程推导出了对舰船机械设备隔振系统动力学研究具有普适性的一般理论模型。     

火炮最优射击稳定性设计研究

为获取最优的后坐阻力规律FR(t)以提高射击稳定性,基于多体系统动力学建模理论,建立了全炮动力学模型;以火炮射击时跳动量最小为目标,节制杆各圆锥段直径为设计变量,基于优化设计方法对优化问题进行了求解。优化结果表明:最大后坐阻力和火炮跳高都小于优化前,后坐阻力曲线更加平缓,火炮射击稳定性得到明显改善。     

虚拟体在弹炮耦合系统动力学模型中的应用

为了更好地研究火炮发射过程中柔性身管和弹丸间的耦合作用,通过引入虚拟体,提出了一种经由虚拟体组成的模拟身管来间接传递弹炮间力元的方法,推导了含虚拟体项的弹炮刚柔耦合动力学方程。以某型火炮为例,引入弹炮系统模型,获得了在相同射击条件下试验测试数据和仿真计算结果的对比曲线,分析表明采用该方法建立的模型实现了弹炮间相互作用力的传递,并且能较真实反映弹丸在膛内的运动规律,为火炮发射动力学研究提供了一定的参考。     

基于虚拟样机的火炮系统建模与仿真分析

根据地火炮的主要部件的连接关系,在分析了火炮拓扑结构的基础上,讨论了火炮各体的自由度。介绍了机械系统动力学仿真分析系统ADAMS,首次将其应用引入到武器装备研究领域,简述了Kane方法建模的步骤。结合Fortran语言编程,在ADAMS环境下建立了火炮虚拟样机,虚拟样机仿真和Kane方法对比结果说明了虚拟样机建立的可信性。最后,研究了驻锄刚度对火炮振动性能的影响,并展望了虚拟样机的应用前景。     

油田拆解装备补偿系统动力学仿真二次开发

该项目基于通用多体动力学仿真软件进行二次开发,建立位移补偿系统动力学仿真模块,通过用户子程序实现位移补偿系统的自动参数化建模,自动施加边界条件,并自动提取铰点位置速度和力的结果数据。通过对超大型海上油田设施一体化拆解装备位移补偿系统进行自动化建模、计算及后处理,建立了一套补偿系统动力学仿真模型,并对不同油缸安装点位置的模型进行动力学仿真,计算油缸载荷及托架移动速度。结果表明该技术可以快速地对位移补偿系统进行多体动力学仿真,并获得仿真结果。     

一种新型火炮后坐体运动参数智能测试系统

本文介绍了一种直接利用ＰＣ机和光栅式光电传感器构成的火炮后坐体运动参数智能测试系统。该系统充分发挥了ＰＣ机在软件编程，运行速度，硬件接口等方面的优势，直接用ＰＣ机测量火炮后坐体在射击过程中的运动位移，速度，加速度等参数。具体结构简单可靠，测试精度高，范围宽等特点。现已成功地应用于某火炮会体运动参数测试系统     

火炮射击训练装置创新设计

为满足某类带自动装弹系统的坦克火炮射击训练需要,结合该新装备的实际情况,本着实用、有效的原则,设计了火炮射击训练装置。新设计的火炮射击训练装置采用了电控自动、螺旋闭锁、转轮弹鼓供弹集壳等新型设计,实现了膛内可控自动工作,满足坦克炮的设计射速,枪机闭锁可靠并有良好的适应性,弹壳能有序收集。整个装置结构简单、易于控制,较好地满足了坦克火炮射击训练装置的设计要求。     

模切机主切机构刚柔耦合动力学特性研究

基于虚拟样机技术和柔性多体动力学理论,综合运用三维建模、有限元分析以及多体动力学仿真等技术,建立了自动平压平模切机主切机构曲轴-连杆-肘杆-动平台系统三维刚柔耦合动力学模型,并对其动态特性进行仿真,得到了一个运动周期各部件运动及动力学响应曲线。结果表明,主切机构运行过程中没有飞脱和腾跳等现象发生。     

通用高炮火控系统教学仿真平台的实现

高炮火控系统作为高炮武器系统的核心组成部分和陆军战术C~3I系统的战术终端,在对空防御系统中起着承上启下的关键作用.故此,基于MATLAB/SIMULINK软件平台设计、开发了通用高炮火控系统教学仿真平台.本文主要介绍该平台的基本组成、实现方法和仿真实现分析等内容.     

A uniform temperature 400°C oven for UHV bake-out

An inexpensive and simple, but sturdy 400°C oven is heated with four 3 kW hot air guns. Due to their plug-in nature, a single set of hot air guns can be used for a number of ovens. The 1500 l/min flow of turbulent hot air keeps the UHV system at a uniform temperature during the bake-out.     

复合射孔技术综述

文章综合分析了复合射孔现有方法和技术,以及各种方法、技术的优点和不足.STIMGUN系统装药量大,作业效果好,避免了炸枪,可使用常规射孔枪;但有时不得不使用小直径射孔器.分体式复合射孔技术药量调整范围较大,不会炸枪,可使用常规射孔枪;不足之处是由于火药装药与射孔段不在同一层,气体利用效率较低.一体式复合射孔技术火药装药与射孔段在同一层位,火药产生的高压气体正对射孔孔道做功,效率高,作业效果好;缺点是装药量少,产气量较低,需使用带泄压孔的特制射孔枪,有时发生炸枪事故.双复射孔器可以适当扩大枪径,提高了射孔枪的承载能力,具有避免炸枪、环空峰压减缓、作用时间加长等特点.     

行进间射击时的动力学研究

本文研究了自行火炮在行进间发射时的动力学问题。用拉格朗日方法建立了自行火炮行进间发射时的动力学方程，并编制了计算机软件，对某自行火炮在随机路面上作行进间射击进行了仿真，预测了该武器系统的动力学特性和动态响应，为该类系统的结构设计和实际应用均有参考价值。     

The development of surface topography using two ion beams

Ion etching is a well-established technique for the micromachining of solid surfaces. It is used extensively in surface analysis with techniques such as Auger electron spectroscopy, ESCA and SIMS, both for surface cleaning and composition—depth profiling. In all of these applications the formation of ion-induced surface topography is a serious problem. Experimental evidence has shown that the use of two ion guns symmetrically inclined about the surface normal can partially ameliorate this difficulty. This paper considers the problem theoretically and shows for model systems the type of topography produced by two guns for various angles of separation. In general, the use of two guns suppresses cone formation and leads to the development of flatter-topped structures. Two guns also tend to undercut impurities which would otherwise lead to massive cone formation using one ion gun. The analysis lends further support to the use of twin ion beams for optimum sputterdepth profiling in surface analysis.     

95式5.8mm班用枪族的研制

主要叙述我国轻武器行业两代工程技术人员在基础很薄弱的情况下,团结合作,用科学和严密的方法,在很短的时间内研制出高水平的步兵班用枪族,使中国步兵枪械达到世界先进水平,受到军方高度评价。该枪族已于1997年元月正式装备驻港部队,并将陆续装备全军。     

Aeroballistic and impact physics research at EMI an historical overview

On the occasion of the Distinguished Scientist Award presentation at HVIS 1992, the technical and scientific promotion of the Impact Physics Division at EMI in the field of aeroballistics, free flight dynamics, terminal ballistics and impact physics is described. This development is closely related to the work of the recipients.

The activities began in the late fifties when a small pressurized ballistic range with a gas gun was built. The problems to construct a well working facility with observation stations are reported that arose, at those early times, from the lack of experience, money and suitable locations. In the mid-sixties, the experimental possibilities were extended by building a two-stage light gas gun that could also be used as a gun tunnel. These facilities have been the foundation for research in the field of free flight aerodynamics, such as the study of near and far wakes behind a blunt hypersonic body or the study of shock wave boundary layer interactions. In 1972, the division took the first step into terminal ballistics and, because of increasing interest, impact physics became the main research area. The division grew and with it the instrumentation. Today, diverse gas guns, powder guns and two-stage light gas guns are in operation. One topic of main interest during the years has been the penetration of rod shaped projectiles. Here the best-known result may be mentioned, the so-called ‘Hohler-Stilp S-shaped penetration curves’. In addition to this, many other topics have been investigated that can be summarized under the title “penetration mechanics and impact physics”. Based on a well developed launching technique and instrumentation, problems were investigated at low velocities of a few hundred m/s, at ordnance velocities and especially at hypervelocities up to 10 km/s. It has been recognized that dynamic material behavior and microstructural effects play an important role in understanding the interaction of projectiles with targets. Therefore, a VISAR, an electronic raster microscope, a Hopkinson bar and further equipment have been installed. Basing on the work of a period of more than 20 years, EMI has come into contact with national and foreign institutions and has become a partner for many cooperations.     

模块化射孔工艺技术

介绍了一种新型射孔完井技术——模块化电缆射孔工艺技术。它采用单芯电缆传输方式,首先将射孔器支撑装置锚定到预定深度,然后将射孔所需全部模块化射孔器分次下入井内,最后引爆射孔弹,从而达到多支射孔器分次下井、一次点火完成的目的。在此基础上,通过特殊的导向装置设计,实现电缆定方位射孔。它的优点是充分发挥了电缆传输方式动用设备少、作业方便、施工时间短等优势,又实现了部分油管输送射孔的功能,如全井负压射孔、防喷等。另外,在高压油气井射孔时,模块化射孔器可自动丢到井底,油气井直接生产,对高压油气不会产生截流。如果想起出井下工具,由于井下工具不长,利用井口防喷管就可完成此项工作。     

Effect of filament heating current on electron beam of directly heated strip-type electron gun

The method of Electron Beam-Physical Vapour Deposition (EB-PVD) for handling large substrates is well established in the metallurgical industry, where sweeping axisymmetric electron guns or multiple pencil guns are routinely used to cover a large target area. The non-uniformity in current density in those methods can be overcome, to a large extent, by using the strip-type electron gun. In this paper, we propose to use an AC-heated strip-type electron gun to cover large target areas. The magnetic field generated by the alternating filament current oscillates the beam in a direction parallel to the filament length, thereby eliminating the need for applying an external electric or magnetic field for sweeping the beam. The non-uniformity in the current density within the strip electron beam, arising due to finite length of the filament, is reduced by the use of dummy filaments on both ends of the active filament. These results are supported by electron trajectory simulations.     

Explosive flux compression generators for rail gun power sources

A class of explosive magnetic flux compression generators is described that has been used successfully to power rail guns. A program to increase generator current magnitudes and pulse lengths is outlined. Various generator loss mechanisms are discussed and plans to control some of them are outlined. Included are various modifications of the conventional strip generators that are more resistant to undesirable expansion of generator components from magnetic forces. Finally, an integral rail gun is discussed that has coaxial geometry. Integral rail guns utilize the rails themselves as flux compression generator elements and, under ideal conditions, are theoretically capable of driving projectiles to arbitrarily high velocities. Integral coaxial rail guns should be superior in some regards to their square bore counterparts.