速率捷联制导系统工具误差分析方法

本文首先介绍速率捷联制导系统工具误差分析的主要内容,接着使用一种新的方法建立了数学模型,并通过一个范例进行了数学仿直.仿真结果证明,本文提出的算法是可信的.     

Static strength analysis of dragonfly inspired wings for biomimetic micro aerial vehicles

This article examines the suitability of fabricating artificial, dragonfly-like, wing frames from materials that are commonly used in unmanned aircraft(balsa wood, black graphite carbon fiber and red prepreg fiberglass). Wing frames made with Type 321 stainless steel are also examined for comparison. The purpose of these wings is for future use in biomimetic micro aerial vehicles(BMAV). BMAV are a new class of unmanned micro-sized aerial vehicles that mimic flying biological organisms(like flying insects). Insects, such as dragonflies, possess corrugated and complex vein structures that are difficult to mimic. Simplified dragonfly-like wing frames were fabricated from these materials and then a nano-composite film was adhered to them, which mimics the membrane of an actual dragonfly. Finite element analysis simulations were also performed and compared to experimental results. The results showed good agreement(less than 10% difference for all cases).Analysis of these results shows that stainless steel is a poor choice for this wing configuration, primarily because of the aggressive oxidation observed. Steel, as well as balsa wood, also lacks flexibility. In comparison, black graphite carbon fiber and red prepreg fiberglass offer some structural advantages, making them more suitable for consideration in future BMAV applications.     

基于CFD动网格的内装式空射分离研究

研究了使用飞机发射运载火箭时的机箭分离过程.提出了一种可以解决内装式空射分离问题的整体解决方案,主要基于CAD三维实体建模方法、多体动力学方法和结合六自由度运动的计算流体力学(CFD)动网格方法.以CFD动网格计算为核心,进行了空射分离过程关键问题的研究,得到了火箭在载机气动干扰环境下的运动特性,为轨道卫星和弹道导弹的快速、廉价发射打下了研究基础.     

Tilts and polarity separation in the sunspot groups and active regions at the ascending and descending phases of the cycle 23

The Solar Feature Catalogues for sunspots and active regions measured with SOHO/MDI instrument and Ca II K3 spectroheliograph of the Paris-Meudon Observatory are analyzed with the automated classification technique for sunspot groups and active region polarities. We report the first classification results for daily variations of tilt angles (normal and trigonometric ones) in sunspot groups (SG) and active (AR) regions in the cycle 23. The average normal tilts are presented for every year at the ascending and descending phases of the cycle 23 which are similar to those deduced by other authors for the cycles 19–22. The normal tilts of both the sunspot groups and active regions are shown to increase in the ascending phase and a decrease in the descending phase. Similar to SG and AR areas, the trigonometric tilts are shown to have the noticeable North–South asymmetry with the Southern hemisphere dominant in the selected ascending and descending periods. The normal tilt variations with latitude follow Joy’s law revealing a periodicity along the meridian of about 10° and reaching the maximum of 14° at the latitude of about 32° corresponding to the top of the ‘royal zone’ where the sunspots appear. The variations of polarity separation with a latitude are in an anti-phase with those of the tilts reaching a maximum at the latitude of 35° and showing a small positive separation for the groups/active regions in a vicinity of the average tilts ±40°. The ratio R of the polarity separation to the trigonometric tilt fits the linear function of a latitude φ as R = −0.0213φ − 0.1245 confirming positive separation for the polarities of active regions with the average tilts, or the dominance of activity in the Southern hemisphere activity, for the selected period of observations.     

关于检修分离的航空维修管理模式探讨

以维修过程中的人因研究为出发点,以“三漏”管理为例,从检修分离的理论依据、实施过程和实践成效等三个方面,尝试探索一种创新的人性化管理模式.     

空气动力对飞机内藏式导弹分离轨迹影响的低速风洞试验研究

在４ｍ×３ｍ低速风洞中研究了空气动力对战斗机内藏式导弹弹射分离轨迹的影响。采用简单网格法测量了导弹在干扰流场中的气动力，进行了分离轨迹估算，用捕获轨迹试验得到了分离轨迹，选定了最佳弹射力参数。试验结果表明，实验导弹安全分离必须采用弹射力，气动俯仰力矩是影响导弹姿态的重要因素，气动力对分离位置影响较小。     

质子交换膜燃料电池驱动直流电机转速性能的动态仿真模型

燃料电池具有能量转化效率高、低噪声、低排放、稳定可靠等优点,被认为是继蒸汽机和内燃机之后的第三代动力系统.燃料电池已经成为无人机、轻型飞机的主动力,并用于大型客机的辅助动力装置.本文设计了应用质子交换膜燃料电池直接驱动直流电机和螺旋桨的方案,并利用Matlab/Simulink构建了仿真模型,模拟燃料电池的动态输出特性以及电动机的转速特性.该模型可以为燃料电池飞行器的研发提供参考数据.     

空中交通中尾流间隔的研究

分析了雷达尾流间隔标准的分类，通过尾流的形成机理和对后机影响的分析，建立了后机的危险遭遇模型和前机的尾流消散模型，给出了在确定的时间间隔下确定尾流危险遭遇概率的方法。     

绕扁长椭球体三维分离的积分法

本文利用三维积分边界层法并结合流线法决定涡层型流动分离。由三维不可压湍流边界层方程求得边界层参数后,按流线法计算粘性流线。作为算例,研究了一带迎角的扁长椭球体在不可压缩湍流里的绕流,经与水洞里所观察到的α=15°流型的对比,二者基本一致。     

惯性组合误差射前等效补偿方法研究

为了解决原有的惯性组合工具误差有修正的不能准确分离加速度计零次项与一次项的缺点，在分析弹道特性和工具误差被偿模型的基础上，提出了加速度计误差射前等效补偿方法，实现了在导弹临射前对纵向加速度计零次项和一次顶误差的等效补偿。