架空线自阻尼的测试方法

自阻尼是导线的基本特性之一。在高压架空导线防振设计中,自阻尼是一个基础数据。本文是介绍对导线自阻尼的三种测试方法。其中的“剪力法”是我们自己研创的新方法。文中不仅介绍了测量技术,还附有在我国第一次测出的 LGJQ-400型导线的自阻尼数据。     

Response regimes of narrow-band stochastic excited linear oscillator coupled to nonlinear energy sink

This paper draws attention to the issue of the vibration absorption of nonlinear mechanical system coupled to nonlinear energy sink(NES) under the impact of the narrow band stochastic excitation. Firstly, based on the complex-averaging method and frequency detuning methodology,response regimes of oscillators have been researched under the linear impact of coupling a nonlinear attachment with less relativistic mass and an external sinusoidal forcing, of which results turn out that the quasi-periodicity response regime of system which occurs when the external excitation amplitude exceeds the critical values will be the precondition of the targeted energy transfer.Secondly, basing on the path integration method, vibration suppression of NES has been researched when it is affected by a main oscillator with a narrow band stochastic force in the form of trigonometric functions, of which results show that response regimes are affected by the amplitude of stochastic excitation and the disturbance strength. Finally, all these conclusions have been approved by the numerical verification and coincided with the theoretical analysis; meanwhile, after the comparing analysis with the optimal linear absorber, it turns out that the NES which is affected by the narrow band stochastic force could also suppress the vibration of system with a better effect.     

摩托车道路工况模拟软件的开发

开发和设计了摩托车道路工况模拟软件，控制摩托车底盘自动化控制设备模拟摩托车行驶时的各种道路工况条件，通过预热、机械损失测量、ALR修正和道路工况模拟四个步骤，在室内实现摩托车型号的道路工况测试。根据DELLPHI和VC的特长进行混合汇编，使用VC为工控板设计了底层的接口程序，通过DELPHI设计工作流程和交互界面，并使用VBA嵌入技术设计灵活的EXCEL报表。     

超高速碰撞数值模拟

本文在耦合欧拉－拉格朗日动参考系中，基于流体弹粘塑性理论，用三维等参元对各向同性材料及正交各向异性材料在超高速碰撞下的动力响应进行了数值模拟。     

几何和流动参数对上翘后体阻力系数的影响

利用N-S方程对9个上翘后体模型进行了气动力计算,主要研究后体几何参数和流动参数对上翘后体阻力系数的影响.研究结果表明, 后体的压差阻力系数分别随上翘角、收缩比的增加及迎角的减小而明显增加;后体摩擦阻力系数分别随后体的长细比的增加和雷诺数的减小而增加;后体越扁平,其压差阻力系数越大;在跨音速时,波阻系数也与上翘角有关,上翘角增加会导致波阻系数进一步加大.     

基于可复用面向对象的航空发动机典型故障管理系统

基于C/S架构,采用UML建模和可复用面向对象技术,开发了航空发动机典型故障信息管理系统。该系统以结构化和网络化的形式保存典型故障模式的基本信息、详细分析信息和相应的故障信息,并提供了方便的查询和输出的功能,具有可用性、灵活性和易扩展性的特征。     

含能材料及相关物的低温焓松驰研究──(Ⅰ)由DSC获得粘弹系数

用差示扫描量热仪（ＤＳＣ）技术研究了某些含能材料及相关物的低温焓松弛过程及时温等效,通过玻璃化转变温度与升温速率的关系,导出了ＷＬＦ方程粘弹系数的计算式,并计算了１０个体系的粘弹系数,实验结果表明,用ＤＳＣ技术可以测定焓松驰和ＷＬＦ方程的系数。     

Application of hybrid regularization method for tomographic reconstruction of midlatitude ionospheric electron density

Reconstructing ionospheric electron density (IED) is an ill-posed inverse problem, with classical Tikhonov regularization tending to smooth IED structures. By contrast, total variation (TV) regularization effectively resists noise and preserves discontinuities of the IED. In this paper, we regularize the inverse problem by incorporating both Tikhonov and TV regularization. A specific formulation of the proposed method, called hybrid regularization, is introduced and investigated. The method is then tested using simulated data for the actual positions of the GPS satellites and ground receivers, and also applied to the analysis of real observation data under quiescent and disturbed ionospheric conditions. Experiments demonstrate the effectiveness, and illustrate the validity and reliability of the proposed method.     

一种新的旋翼动态尾迹模型研究

针对直升机大机动实时飞行仿真的需求，提出了一种新的旋翼动态尾迹模型，并开展了初步的验证研究。该模型采用涡环单元来表示旋翼尾迹涡系，每个涡环具有5个刚体运动自由度和1个半径伸展收缩自由度，可描述大机动飞行中旋翼尾迹的拉伸、压缩、倾斜、弯曲等动态畸变行为，并给出桨盘或空间任意区域的旋翼尾迹瞬态诱导速度分布。以悬停状态旋翼拉力和俯仰角速度阶跃突增为算例，通过与尾迹畸变增广的Pitt-Peters动态入流模型的对比分析，验证了本文模型的正确性和实时性，并得到了一些新的结论。     

基于航天器复杂动力学模型的鲁棒H_∞振动抑制算法

现代大型航天器柔性越来越大,为了获得更好的姿态控制性能,需要主动振动抑制.鲁棒Η∞是一种正在走向工程应用的控制器设计方法,DGKF解析法,线形矩阵不等式LMI数值法,定阶Η∞范数优化法是3种重要的算法.本文对国际空间站俄罗斯舱的有限元模型提出了振动抑制的Η∞综合问题,分别用3种算法求解鲁棒Η∞控制器.基于DGKF法的全阶次优控制器,存在零极点对消,而基于LMI法的51控制器光滑,能有效抑制零极点对消,但LMI法不是一种优化算法,两种控制器降阶为2阶时,Η∞性能衰退大于80%.基于定阶法的2阶控制器和PI控制器具有与DGKF全阶控制器相近的Η∞性能,鲁棒性分析和扰动抑制的时域仿真验证了上述结论.