基于隐身的三维航迹规划研究

为提高飞行器对地攻击效能,必须对其三维航迹规划技术进行研究。考虑到威胁并非不可穿越,建立了间歇式暴露模型;通过考虑飞行器姿态变化对暴露范围的影响,建立了飞行器战术隐身模型;对传统稀疏A*算法进行了改进,有效提高了规划速度,在此基础上提出了具有实时规划能力的分步规划算法,并给出了解决在线重规划的方法;最后,在真实地形下进行了仿真验证,仿真结果证明了所建模型及算法的有效性和实用性。     

超高强度钢起落架锻造成形仿真与工艺试验

采用Deform 3D有限元软件对23Co13Ni11Cr3Mo超高强度钢起落架锻造成形过程进行了数值模拟,研究了不同工艺参数对起落架成形的影响。通过锻造成形实验,验证工艺方案的可行性及合理性。研究结果表明:适当增加变形温度,可有效降低材料的变形抗力,增强材料在模腔中的流动性;成形速度影响锻件的变形均匀性,减小成形速度可以改善飞机起落架的性能。     

民用飞机动力装置系统FHA研究

将功能危害性评估方法引入动力装置系统的安全性评估中,并以某型飞机动力装置系统为例,具体介绍了评估功能危害性的过程,为民机动力装置系统安全性评估提供一定参考。     

倾转旋翼机气动设计技术

针对倾转旋翼机气动技术进行了研究,包括过渡状态旋翼动态尾迹和非定常气动特性研究、过渡状态旋翼/机翼气动干扰特性研究以及倾转旋翼机模型风洞试验。建立了过渡状态旋翼动态尾迹和非定常气动特性以及旋翼/机翼气动干扰特性的理论分析方法,通过对比公开发表的试验数据和本研究获得的风洞试验结果验证了方法的有效性。     

基于模糊理论老龄飞机结构腐蚀损伤评判

对老龄飞机在复杂环境发生结构腐蚀损伤的情况进行综合评判,提出了一种基于故障树分析的手段和理论方法.通过举例分析,证明所提方法的有效性.     

民用飞机驾驶员设计眼位研究

依据驾驶舱布局设计标准,对民用飞机驾驶员设计眼位进行研究,设计民用飞机驾驶员设计眼位设计流程,供驾驶舱布局设计人员参考.     

Approximate Nonlinear Modeling of Aircraft Engine Surge Margin Based on Equilibrium Manifold Expansion

Stable operation of aircraft engine compressions is constrained by rotating surge. In this paper, an approximate nonlinear surge margin model of aircraft engine compression system by using equilibrium manifold is presented. Firstly, this paper gives an overview of the current state of modeling aerodynamic flow instabilities in engine compressors. Secondly, the expansion form of equilibrium manifold is introduced, and the choosing scheduling variable method is discussed. Then, this paper also gives the identification procedure of modeling the approximate nonlinear model. Finally, the modeling and simulations with high pressure (HP) compressor surge margin of the aircraft engine show that this real-time model has the same accuracy with the thermodynamic model, but has simpler structure and shorter computation time.     

民机中央翼加筋壁板承载能力的非线性有限元分析

应用非线性有限元分析技术,采用MSC.Patran为前后置处理器进行建模,以具有较强非线性功能的Marc软件为求解器,细致研究了某民机中央翼加筋板结构在受力状态下的非线性变形、后屈曲破坏过程、最终失稳破坏形式及载荷,与试验结果进行了比较,破坏过程及破坏形式与试验相吻合,计算的破坏载荷与试验的破坏载荷误差在5%以内,显示文中方法可以满足工程设计和分析要求。     

直升机起落架的集成计算

直升机起落架常规计算包括停机状态计算及减缩质量计算、静态性能计算及主、尾起落架的着陆性能计算.要完成这些计算需要整机及起落架的诸多数据.在研制过程中,为了获得最优的设计,需要对起落架的各参数进行不断调整,对计算结果进行反复分析和比较,计算量较大,数据处理较为繁复耗时.详细阐述如何采用Excel和Matlab对起落架的常规计算进行集成.为完成一种直升机起落架的常规计算,采用该集成方法,编制了2000余行的M代码.在惠普Z800计算机平台下运行,耗时400余秒即可完成所有相关计算.输入输出的数据存储在同一Excel文件,文件中各项参数和计算结果数据可直接用于查阅、校对、分析,也可再编辑.     

Control strategies for aircraft airframe noise reduction

With the development of low-noise aircraft engine, airframe noise now represents a major noise source during the commercial aircraft’s approach to landing phase. Noise control efforts have therefore been extensively focused on the airframe noise problems in order to further reduce aircraft overall noise. In this review, various control methods explored in the last decades for noise reduction on airframe components including high-lift devices and landing gears are summarized. We introduce recent major achievements in airframe noise reduction with passive control methods such as fairings, deceleration plates, splitter plates, acoustic liners, slat cove cover and side-edge replacements, and then discuss the potential and control mechanism of some promising active flow control strategies for airframe noise reduction, such as plasma technique and air blowing/suction devices. Based on the knowledge gained throughout the extensively noise control testing, a few design concepts on the landing gear, high-lift devices and whole aircraft are provided for advanced aircraft low-noise design. Finally, discussions and suggestions are given for future research on airframe noise reduction.