某大口径迫榴炮同时弹着的理论分析

采用同时弹着射击方式旨在提高火炮的突袭威力,其威力的提高程度取决于同时弹着的射弹数量.用经典外弹道模型对某大口径迫榴炮的主配弹种迫弹、榴弹和预制破片弹各装药号的最大射程范围进行了计算,从理论上分析了不同射程同时弹着的射弹数量;分别对3个弹种的不同装药号进行了射距5 km的外弹道计算,在满足该炮同时弹着方案选择条件的前提下,确定了严格同时弹着的射击方案.结果表明,多弹种混合同时弹着在射弹数量方面更具优势.某大口径迫榴炮由于射角变化范围大、配备弹种多,因此是比较适合采用同时弹着射击方式的炮种之一.     

利用随行装药技术实现超高速发射的探讨

在探讨了运用常规方法实现超高速发射的基础上,该文着重讨论了固体随行装药(STC)技术,完成了相应的弹道摸底试验.在某30mm火炮上使质量为57g的弹丸获得了大约2115m/s的初速,在最大膛压相当的情况下,初速增加了近100m/s,初步显示了随行装药(TC)技术提高火炮初速的弹道效果,并且还有很大的增速潜力.     

采用包覆随行装药提高炮射导弹内弹道性能的数值预测

在不增加过载的情况下,为了提高炮射导弹发射初速,提出采用包覆随行装药的火炮装药结构。建立了包含半可燃药筒在内的混合装药内弹道模型,主装药选取高能钝感发射药,随行装药利用低燃速药进行包覆处理,分析了不同随行率和包覆层厚度条件下内弹道性能变化。计算结果表明:在一定范围内,随着随行率的增加,弹丸初速提高;通过改变包覆层厚度能够很好地控制随行装药点火延迟时间。     

基于非层次型改进二级求解技术的大口径火炮多学科优化设计

以某大口径火炮为研究对象,研究该火炮弹-炮-药一体化设计中弹、炮、药参数的更优匹配关系。基于内弹道、外弹道及终点效应3个子学科的内部耦合关系,以弹丸最大初速、火药利用效率、射程及杀伤面积为优化目标,借助Isight集成优化平台,采用非层次型改进二级求解策略,建立了系统学科及某大口径火炮弹-炮-药一体化多学科优化模型。相比于传统的单目标优化方法,该模型充分发挥了各个子学科的自治能力,借助系统学科的统筹协调,避免了优化目标的过度劣化,实现了火炮综合性能的改善。     

埋头弹随行装药内弹道性能的数值分析

为研究埋头弹火炮的更优性能,基于2次点火及火药程序燃烧控制技术,建立了埋头弹固体随行装药内弹道零维模型。针对某埋头式榴弹的试验结果进行了数值模拟,获得的初速、膛压变化规律与实测结果相吻合。在此基础上,数值分析了加载随行装药后多参数变化对埋头弹火炮内弹道性能的影响。结果表明,在最大膛压不变的条件下,随行装药可提高炮口初速6%; 随行装药量、燃速系数及点火延迟时间三者合理优化匹配,才能实现最佳的内弹道性能。     

某大口径火炮两相流内弹道模拟

为了掌握大口径低膛压火炮初速或然误差的影响因素，建立了某大口径火炮两相流内弹道模型并完成了数值模拟。通过模拟装药分布、弹丸挤进过程、点火过程对火炮初速的影响，了解各种装药因素对火炮初速或然误差的影响程度。所得结果为进一步优化装药结构，提高初速稳定性提供参考。     

水下炮内弹道分析与数值仿真

为提高火炮在水下发射的初速，水下炮炮口设有挡水板，发射时挡水板改变了膛内弹丸的受力状况。通过水下炮发射时弹丸膛内的受力分析，考虑射弹前方压缩空气形成的激波压力，结合经典内弹道理论，建立了水下炮内弹道模型。以某口径水下炮发射为例进行了数值仿真，得到水下炮的膛压和速度曲线，与传统火炮对比，变化趋势基本一致，但膛压略有增大，初速有所减小；仿真还得到水下炮弹前激波压力曲线，仿真结果与实验结果吻合。     

120mm反坦克炮采用随行装药提高初速的理论研究

采用两相流内弹道方法，对１２０ｍｍ反坦克炮随行装药方案提高初速问题进行了理论研究。建立了两种随行装药方案，即粘结式和包容式条件下边界条件方程组，并进行内弹道数值分析。在最大压力、弹重、弹丸行程不变的假定条件下，当随行药为全部装药质量的３０％时，包容式可提高初速１１６ｍ／ｓ，即６．７％；而粘结式只能提高６６ｍ／ｓ，即３．８％。最后，就随行装药提高初速的可能性和必要条件作了讨论。     

固体随行装药内弹道模型及数值模拟

随行装药点火燃烧在整个火炮内弹道过程中具有独特性，有必要开展随行装药内弹道过程的理论研究，为工程应用提供理论指导。采用包容式固体随行装药方案，利用新研制的点火延迟机构，考虑了弹丸的变质量问题。在实验的基础上，建立了固体随行装药的内弹道零维模型，并与常规装药进行了对比，预测了弹后空间特征参数的变化规律。采用模型编写的计算软件计算结果与30mm弹道炮的实验结果进行比较可以看出，计算的P-t曲线与实测的P-t曲线具有较好的一致性。建立的数学物理模型的处理方法行之有效，可以用来指导随行装药的设计。     

地面火炮射程的外弹道优化设计

本文以射程为优化目标,对火炮弹丸在全弹道上从气动力、外弹道等诸性能方面进行了系统综合优化,同时,对火炮、弹丸外弹道优化理论中的一些问题进行了探讨,建立了优化设计数学模型,并采用数学规划方法求解,编制了相应的计算程序。利用该计算程序,只要根据下达的设计任务输入一些已知参数(如炮口能量、膛线缠度等),就可对弹丸最大射程的外弹道优化设计进行计算,给出最佳的弹重、初速、弹形参数等主要设计参数。文中还对175mm火炮弹丸进行了优化设计计算,并与原方案进行了比较.另外,利用该程序还可进行优化计算在满足一定射程时所需的最小炮口能量。     

Expert Systems Aimed at General Design of Projectiles

Expert systems aimed at the general design of projectiles can implement a series of intelligent designs, such as the design of HE shell, the scheme expounded and proved, the emulation analysis and calculation, etc. Aiming at the product design feature, the expert system adopts the object-oriented knowledge representation and all kinds of inference control engines to describe and reason the relevant knowledge regarding the product through the microcomputer. It embodies the foundation of emulation analysis and simulated manufacturing of the shell. It makes use of the method that knowledge expression is combined with condition of inference to carry out the overall design and emulation and reference.The paper gives the ways through which the functions can be achieved, gives the modularization of reference and the design methods of systematization, puts forward the method of knowledge expression and working interface, and supplies a platform for similar products of the shell category that can be quickly designed.     

Parameter Identification for the Valve Control Cylinder System of a Hydraulic Manipulator

In mechanical, hydraulic and electronic systems, the determination of system parameters is often challenging because liquid parameters often change significantly, due to variations in working and environmental conditions. Therefore, it is of significant practical importance to identify those parameters through experimental procedures. A systematic approach to identifying parameters in the valve controlling cylinder system of hydraulic manipulators is provided. It first derives the transfer function of the system, and then uses P control of PID control to predict system parameters. The predicted parameters are further validated using PID control. The prediction through simulation using MatLab language is utilized, which agrees well with experimental results.     

Three-dimensional Numerical Simulation of Combustion Field in the Combustion Chamber

In order to study the effect of rotation on the combustion in the underwater vehicle, a two-phase turbulent combustion process is described with Reynolds stress turbulence model, eddy-dissipation turbulent combustion model, P-1 radiation model and particle tracking model of liquid. The flow in the rotating combustion chamber is simulated at two different working speeds, 0 r/min and 1 000 r/min by Fluent software. The temperature, gas velocity, static pressure of wall and fuel concentration are computed and compared. The results show that the combustion in rotating combustor is faster and more effective.     

Software Communication Architecture Implementation and Its Waveform Application

This paper attempts to do a research on the development of software defined radio（SDR） based on software communication architecture（SCA）. Firstly, SCA is studied and a whole reference model of SCA3.0 core framework （CF） is realized; Secondly, an application-specific FM3TR waveform is implemented on the platform of common software based on the reference model; Thirdly, from the point of view of real-time performance and software reuse, tests and validations are made on the above realized CF reference model and FM3TR waveform. As a result, the SCA-compliant SDR has favorable interoperability and software portability and can satisfy the real-time performance requirements which are not too rigorous.     

Dynamic Simulation of the Tank Gun Recoil Response

By using the ATV module of MSC. ADAMS, the dynamic simulation of recoil response of tank gun is analyzed.How the recoil force affects the bodywork and the suspension during gun firing, as well as the changing status of the gun muzzle‘s velocity are gained. All results and analyzing methods are offered for the designing basis of optimizing tank vehicle-gun match. The constructive exploration is beneficial to improving the general capability of tank.     

Survey of Controllable Suspension System for Off-road Vehicles

The controllable suspension system can improve the performances of off-road vehicles both on road and cross-country. So far, four controllable suspensions, that is, body height control, active, semi-active and slow-active suspensions, have been developed. For off-road vehicles, the slow-active suspension and the semi-active suspension which have controllable stiffness, damping and body height are more appropriate to use. For many years, some control methodologies for controllable suspension systems have been developed along with the development of modern control theory, and two or more original control methods are integrated as a new control method. Today, for military or civilian off-road vehicles, the R&D of controllable suspension systems is ongoing.     

Finite Element Analysis of Fretting Behavior Between an Engine Cylinder Block and a Main Bearing Cap

The finite element analysis of the fretting behavior between a cylinder block and a main bearing cap is presented. The stresses, relative fretting slip, fretting friction work parameter W and crack initiation location parameter G on the fretting contact surface of the cylinder block are obtained and analyzed. It shows that the fretting fatigue problem of the cylinder block can be quantitatively explained by W or G. The effects of pretightening force, friction factor and material combination of the cylinder block and the main bearing cap are studied. The computational results indicate that the fretting fatigue of the cylinder block can be allayed by increasing the elastic modulus of the cylinder block, but not by changing the other two factors.     

An Efficient Key Agreement Framework to MANET

Protocols for key management are compared and evaluated from the point of view on mobile ad hoe networks （MANET）. The issues of fault-tolerance and efficiency of key distribution protocols for group communications in MANET are addressed. Most key distribution protocols existing today are primarily designed for wlre-line networks. These protocols either fail to work as intended or cannot work at all when they are applied to the demanding environment of MANET. Parameters and performance of different protocols are analyzed, and then a fiat is given out, on which new protocols or existing ones are designed and modified, so that they can be robust, scalable and efficient in MANET.     

A Physical Model of Electromagnetic Force from PEMA Acted on Metal Projectiles

Electromagnetic armor is a new conceptual combat vehicle technology, which improves remarkably the defensive capability and maneuverability of vehicles. The authors present definitely to apply the electromagnetic theory to analyze the electromagnetic armor. Based on electromagnetics, the experienced expression of projectile and the physical model of PEMA （passive electromagnetic armor） are obtained when electric current flows through the system, and a computer sim- ulation is given.     

The Kinematics Analysis of the Hydraulic Mine-clearing Mechanical Manipulator

Through analyzing the kinematics of the hydraulic manipulator operating system, according to the rules for set-ing up the D-H coordinate system, the generalized coordinate of the manipulator system is established. The rotating and moving joints are selected from the mechanism as joint variables. Each generalized transformation matrix of joints is worked out. The kinematics equation at the finger end of the manipulator is calculated. The obverse solution for the manipulator is gained. The geometrical operating parameters and primary technical specification of the manipulator system are simulated through the computer. The simulative result has shown that the manipulator operating system meets the working task requirements. This research provides theoretical basis for optimizing structural parameters of the manipulator operating. So it also is justified the feasibility for mechanical manipulators to be used in the engineering equipment platform of the hydraulic excavator.