双翼金属圆柱体散射场的整体计算

本文利用keller的几何绕射理论（GTD）推求出双翼金属圆柱体散射场高频快收敛整体解，弥补了传统分离解（把系统分解为一个金属圆柱和两个金属半平面，分别求解再简单迭加）的不足之处，最后，给出了整体解和分离解的散射电场的模值数值计算结果。     

NASA开发亚声速研究验证平台

实验空气动力学的研究工作主要依托风洞试验进行。由于条件限制,风洞试验往往需要采用缩比模型,这样可能导致尺寸效应等问题的发生,无法模拟真实情况下的雷诺数、噪声等级和边界条件等,造成试验测试结果的失真。飞行研究试验平台的出现为解决这类问题创造了条件。     

Reachable set modeling and engagement analysis of exoatmospheric interceptor

A novel reachable set(RS) model is developed within a framework of exoatmospheric interceptor engagement analysis. The boost phase steering scheme and trajectory distortion mechanism of the interceptor are firstly explored. A mathematical model of the distorted RS is then formulated through a dimension–reduction analysis. By treating the outer boundary of the RS on sphere surface as a spherical convex hull, two relevant theorems are proposed and the RS envelope is depicted by the computational geometry theory. Based on RS model, the algorithms of intercept window analysis and launch parameters determination are proposed, and numerical simulations are carried out for interceptors with different energy or launch points. Results show that the proposed method can avoid intensive on-line computation and provide an accurate and effective approach for interceptor engagement analysis. The suggested RS model also serves as a ready reference to other related problems such as interceptor effectiveness evaluation and platform disposition.     

流量系数可控弹性自适应高超进气道研究

为实现采用气动变几何的设计思想使高超进气道在宽马赫数范围内控制流量系数的目的,针对二元进气道,采用数值计算的方法,通过改变压缩面的上下压差使压缩面产生弹性变形,从而控制不同马赫数下进气道的流量系数。数值计算结果表明,在非设计点来流马赫数为4.5,5.0,5.5条件下,流量系数的可控范围分别为0.787~0.889,0.856~0.972,0.923~1.000,各马赫数所对应的最大流量系数分别比定几何条件下提高了14.2%,13.7%,7.4%,并对出口截面的总压恢复系数也略有提升。由此证明,气动变几何的设计思想是可行的,可以实现在宽马赫数范围内控制流量系数的目的。     

Mechanical properties study of particles reinforced aluminum matrix composites by micro-indentation experiments

By using instrumental micro-indentation technique, the microhardness and Young's modulus of SiC particles reinforced aluminum matrix composites were investigated with microcompression-tester(MCT). The micro-indentation experiments were performed with different maximum loads, and with three loading speeds of 2.231, 4.462 and 19.368 mN/s respectively. During the investigation, matrix, particle and interface were tested by micro-indentation experiments. The results exhibit that the variations of Young's modulus and microhardness at particle, matrix and interface were highly dependent on the loading conditions(maximum load and loading speed) and the locations of indentation. Micro-indentation hardness experiments of matrix show the indentation size effects, i.e. the indentation hardness decreased with the indentation depth increasing. During the analysis, the effect of loading conditions on Young's modulus and microhardness were explained. Besides, the elastic–plastic properties of matrix were analyzed. The validity of calculated results was identified by finite element simulation. And the simulation results had been preliminarily analyzed from statistical aspect.     

国防科技工业计量培训考核资料

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一种外并联式TBCC变几何进气道的设计

对一种Ma=0～7的二元外并联式TBCC变几何进气道设计开展了研究,给出了进气道总体设计思路、气动型面设计过程、变几何调节规律以及流场控制方案。初步数值仿真结果表明,该进气道满足预期的流量捕获需求,高速通道Ma=4和Ma=7时的喉道总压恢复系数分别为0.62和0.45,低速通道Ma=2.3和Ma=4时的喉道总压恢复系数分别为0.97和0.73;该变几何进气道在模态转换过程可以正常工作,没有明显的流动分离出现;由于侧板溢流,三维计算结果下的总压恢复系数与流量系数略低于二维计算结果。对三维外并联TBCC变几何进气道开展了涡轮通道扩压段设计及数值仿真研究,给出了三维模型的气动特性及涡轮通道的反压特性。     

一种用于空间翻滚目标接近控制的相对运动建模方法

针对空间翻滚目标等一类相对运动复杂的接近控制问题，首先重点研究了基于微分几何理论的相对运动建模，建立视线旋转坐标系下的三维相对运动方程；然后将三维相对运动解耦为视线瞬时旋转平面内的相对运动和该平面的转动，建立了统一的控制器设计框架，形式统一简洁、物理意义明确，消除传统制导与控制策略中俯仰、偏航通道的耦合因素影响；最后通过六自由度仿真算例证明，相对运动模型物理意义明晰、鲁棒性强、控制精度高、工程实现容易。