小迎角超音速弧形翼空气动力学特性研究

为了进一步研究弧形翼在小迎角超音速下的空气动力学特性,采用FLUENT软件对弧形翼的超音速三维绕流流场进行数值模拟。数值计算模型采用层流模型,离散格式为三阶MUSCL格式。计算来流马赫数取2.5～5.5,迎角取0°～8°。数值模拟结果给出了弧形翼流场激波波谱、表面压力分布等流场特性,重点分析零迎角下弧形翼产生升力的原因,得出了弧形翼在不同马赫数下,其升力系数、阻力系数随迎角变化的规律。     

格栅翼的气动特性研究评述

格栅翼是一种新型舵翼，研究表明，格栅翼作为飞行器的稳定面和控制面，在升力特性、铰链力矩特性和外形尺寸方面都优于传统平板翼，因而受到国内外研究者的普遍关注．本文着重介绍了国内外进行格栅翼气动特性研究的研究方法、研究内容、主要研究结果和应用情况．     

高超声速轴对称机身-机翼布局翼身干扰分析

为研究高超声速轴对称机身-机翼布局的翼身干扰特性，选择窄条翼和中单翼两种典型组合体布局作为研究对象，从流场和气动力两个方面对其进行系统研究。结果表明：相比于无机翼干扰的轴对称机身，位于机翼斜激波区的机身腹部压力更高，且机翼阻断了高压气流的“上洗”运动，减小了机身背风面压强，机身获得了更多升力；相对于无机身干扰的机翼，中单翼由于与头锥激波发生干扰获得更多升力，而窄条翼处于膨胀区内，其升力小于无翼身干扰时窄条翼升力；机身-机翼布局的升力大于单独机翼与单独机身的升力总和。     

四边形格壁后掠式栅格翼气动特性研究

格壁剖面形状不同的栅格翼其升力性能也大有不同,前期研究表明菱形剖面和四角形剖面栅格翼比矩形剖面栅格翼减阻能力更好.文中基于此对后掠45°的栅格翼进行数值模拟研究,结果表明,投影尺寸相同的3种四边形后掠式栅格翼与其正置式相比均能够有效提高升力,增大升阻比,并且菱形和四角形剖面后掠式的栅格翼气动特性均优于矩形剖面后掠式栅格翼.     

船舶零航速减摇鳍升力仿真研究

应用船舶减摇鳍在零航速时进行减摇，与传统减摇理论有着本质的不同。为了研究船舶零航速减摇鳍在零航速时产生升力的过程，以Weis- Fogh理论为基础，建立了零航速减摇鳍升力模型，对哈尔滨工程大学研制的NJ5型减摇鳍升力模型进行了仿真研究，并应用计算流体力学软件，针对NJ5型减摇鳍进行了数值计算，结果表明数值计算与仿真结果一致，为以后进行水动力试验以及控制规律的进一步研究打下了基础。     

扑翼翼型流体动力特性数值计算与分析

利用对海洋生物运动方式及其运动器官的研究开发水下扑翼推进装置是仿生推进技术的一个重要研究方向。本文通过数值计算方法,以对称翼型为主,开展对扑翼翼型的推力和升力特性的研究,分析了各翼型在不同斯德鲁哈数下的力学表现,以及翼型和相关参数对扑翼推进效果的影响。计算结果表明,翼型扑翼运动时的最大推力系数、平均推力系数和最大升力系数3个参数均与中心弦长比成线性递减关系,翼型参数和工况对翼型的推力和升力特性均有不同程度的影响。     

一种改进折叠弹翼结构设计与气动分析

对圆筒式装载发射的导弹，尾翼的设计是导弹总体结构设计的关键之一。本文提出了一种新型的折叠尾翼结构形式，对这种结构形式的折叠机构进行了详细的机械设计。进一步对设计的导弹外形进行空气动力学数值模拟仿真，并用有限元素法对导弹安定面进行了强度分析。新型对称弧形弹翼与以前弧形张开式弹翼比较提高了横向稳定性。     

固定翼二维弹道修正引信升力翼面位置的影响

固定翼二维弹道修正引信研究需要了解翼面之间的气动干扰。鉴于查不到相关文献,采用流场计算中广泛使用的数值模拟方法,计算引信及翼面的气动参数和修正弹的流场分布。计算结果表明,在固定翼二维弹道修正引信翼面尺寸和安装角度不变的前提下,随着升力翼面安装位置的前移,固定翼二维弹道修正引信的导转力矩、导转翼面的阻力和导转力矩以及升力翼面的阻力和升力均有所增加,而对导转翼面升力的影响较小;在跨音速时,引信及翼面的气动参数均变化较大。     

仿生扑翼推进装置仿真研究

针对新型仿生扑翼推进装置的特点，进行了机构动力学分析。依据扑翼产生升力和推力的机理，并利用ADAMS软件建立了仿真模型。针对不同扑翼面积和扑翼不同的运动速度两个参数对仿生扑翼推进装置产生升力的影响进行了仿真，对结果进行了分析，得到了一些有价值的参数。     

不同后掠形式栅格翼气动特性的研究

栅格翼是一种较之传统翼具有诸多优点的新型的多面翼,但是栅格翼的主要缺点是阻力大。前期研究表明,栅格翼后掠能有效减小阻力。文中基于此对不同后掠形式的栅格翼进行了数值模拟。结果表明,在超声速阶段前缘后掠削尖模型能更有效的减小阻力;升力方面,在不同的马赫数范围,前缘后掠、前缘后掠削尖及整体后掠基础上的前缘后掠都有较好的升力特性;总体来讲,在文中前缘后掠削尖模型的升阻比最大,表现出最好的气动特性。     

Stability of the Third Generation Intensifier under Illumination

The stability under illumination of transmission-mode GaAs photocathode sealed in the third generation intensifier is investigated by use of spectral response testing instruments. The variations of spectral response with the illumination times under weak and intense illumination are compared. The variations of photoemission performance parameters are also characterized. The results show that during initial several weak illuminations photocathode behaves no evident decay and a maximum sensitivity is achieved, while under intense illumination the sensitivity of photocathode begin to decrease largely at the first illumination. The calculated performance parameters show that the variation of surface escape probability with illumination times is a direct cause of instability of photocathode. It is also found that under intense illumination peak wavelength is moved towards short-wave and peak response is decreased, which shows that the ability of long-wave response of photocathode is decreased.     

Open Rule-setting System Applied to Conceptual Design of Engines

Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.     

Research on Linux Network Device Driver

By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux （kernel version 2.6.11 ） is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.     

Passive Acoustic Radar for Detecting Supersonic Cruise Missile

A Passive Acoustic Radar is presented as a necessary complement to electromagnetic wave radar, which will be expected to be an effective means for detecting cruise missiles. Acoustic characteristics of supersonic flying projectiles with diverse shapes are expounded via experiment. It is pointed out that simulation experiment could be implemented using bullet or shell instead of cruise missile. Based on theoretical analysis and experiment, the ““acoustic fingerprint““ character of cruise missile is illustrated to identify it in a strong noise environment. After establishing a locating mathematical model, the technique of acoustic embattling is utilized to resolve a problem of confirming the time of early-warning, considering the fact that velocity of sound is much slower than that of light. Thereby, a whole system of passive acoustic radar for detecting supersonic cruise missile is formed.     

Algorithm for Multi-laser-target Tracking Based on Clustering Fusion

Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.     

Super-resolution Restoration of Remote-sensing Images

A novel image restoration scheme, which is super-resolution image restoration algorithm Poisson-maximum-afterword-probability based on Markvo constraint （MPMAP） combined with evaluating image detail parameter D, has been proposed. The advantage of super-resolution algorithm MPMAP incorporated with parameter D lies in the fact that superresolution algorithm MPMAP model is discrete, which is in accordance with remote-sensing imaging model, and the algorithm MPMAP is proved applicable to linear and non-linear imaging models with a unique solution when noise is not severe. According to simulation experiments for practical images, super-resolution algorithm MPMAP can retain image details better than most of traditional restoration methods; at the same time, the proposed parameter D can help to identify real point spread function （PSF） value of degradation process. Processing result of practical remote-sensing images by MPMAP combined with parameter D are given, it illustrates that MPMAP restoration scheme combined PSF estimation has a better restoration result than that of Photoshop processing, based on the same original images. It is proved that the proposed scheme is helpful to offset the lack of resolution of the original remote-sensing images and has its extensive application foreground.     

Design and Simulation of TF and TA Controller for Missile

A nonlinear terrain following(TF) and terrain avoidance(TA) controller is proposed for missile control systems. Based on classical TF algorithm (adaptive angle method), a new method for TF controller is proposed by using angle of attack. A method of obtaining terrain outline data from digital elevation map (DEM) for TF control is discussed in order to save store space. A TA algorithm is proposed by using bank-to-turn technique. The block control model, which is suitable for backstepping design, is given for nonlinear model of missile. Making full use of the characteristics of the system and combining block control principle and backstepping technique, a robust controller design method is proposed. Uncertainties in every sub-block are allowed, and can be canceled by using the idea of nonlinear damping. It is proved that the state tracking errors are converged to a neighborhood of the origin exponentially. Finally, nonlinear six-degree-of-freedom simulation results for the missile model are presented to demonstrate the effectiveness of the proposed control law.     

Design and Analysis of Test Schemes of Static Postponing Time on Shrapnels Used to Riot Control

The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and three kinds of pressures,the consumed ammunitions are more excessive. Statistic analysis and tentative checkout about a lot of test data are done,feasibility gists are put forward for optimizing of the test design scheme. The optimizing design and data analysis of test scheme of the item are done by managing uniformity design theory, two scientific and reasonable six-point test schemes are confirmed. The feasibility and reliability of the optimizing design schemes put forward above are proved ulteriorly by test validating. The gained schemes not only have good design uniformity and little ammunition wastage and meet the test demand, but also have better forecast ability for the result data of other points using the mathematic models from the actual test points.     

Influence of Installing Error on the Surface Shape Precision of the Axial Symmetry Aspheric Workpiece in Lapping

A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.     

Experimental Research on Output Performances of Giant Magnetostrictive Actuator

The paper introduces the performances of magnetostrictive actuators and its applications, discusses the design methods for the structure and internal magnetic circuit of a giant magnetostrictive actuator, and makes tests on the output displacement and force characteristics for an actuator using homemade magnetostrictive material. The experimental result shows that the actuator has satisfactory output precisions and ranges in transient and stable states, and can be used in lowfrequency vibration control system of precise equipment.