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211.
Plasma of the free burning electric arc between Ag–SnO2–ZnO composite electrodes as well as brass electrodes were investigated. The plasma temperature distributions were obtained by Boltzmann plot method involving Cu I, Ag I or Zn I spectral line emissions. The electron density distributions were obtained from the width and from absolute intensity of spectral lines. The laser absorption spectroscopy was used for measurement of copper atom concentration in plasma. Plasma equilibrium composition was calculated using two independent groups of experimental values (temperature and copper atom concentration, temperature and electron density). It was found that plasma of the free burning electric arc between brass electrodes is in local thermodynamical equilibrium. The experimental verification of the spectroscopic data of Zn I spectral lines was carried out.  相似文献   
212.
通过一系列实验和数据,讨论用磁化率计法测量砝码磁性时各测量分量对砝码磁化率测量结果的影响,并着重分析了砝码几何形状修正因子的测量与确定,比较不同测量方式的特点,以求减少砝码磁性测量时的误差。  相似文献   
213.
The requirements for skid landing gear static strength ensuring are examined based on the comparative analysis of the Airworthiness Standards requirements. Probabilistic principle of determining the safety factor of the skid landing gear is presented. The analysis of the experimental data on bench and flight tests is performed for calculating the actual value of this factor.  相似文献   
214.
The discretization of the boundary value problem for laminated composite shells is based on the finite difference approach using the regular mesh with the constant grid step and the difference operators of the second order of accuracy. The dynamic relaxation method is proposed for the solution of the nonlinear problem. The evolutionary equations of the dynamic relaxation are constructed, and the optimum parameters of the converging linear iterative process are estimated.  相似文献   
215.
This paper presents a brief review of activities in laminar flow control being performed at the Central Aerohydrodynamic Institute named after Prof. N.E. Zhukovsky (TsAGI). These efforts are focused on the improvement of the existing laminar flow control methods and on the development of new ones. The investigations have demonstrated the effectiveness of aircraft surface laminarization applications with the aim of friction drag reduction. The opportunity of considerable delaying of laminar-turbulent transition due to special wing profile geometry and using boundary layer suction and surface cooling has been verified at sub- and supersonic speeds through various wind tunnel testing at TsAGI and during flying laboratory experiments at the Flight Research Institute (LII). The investigations on using hybrid laminar flow control systems for friction drag reduction were also carried out. New techniques of laminar flow control were proposed, in particular, the method of local heating of the wing leading edge, boundary layer laminarization by means of receptivity control, and electrohydrodynamic methods of boundary layer stability control.  相似文献   
216.
For an interception strategy of a removable target by a return space vehicle (RSV), we propose a structure of the control law by the aerodynamic efficiency that determines a chain of the three standard trajectories: nosing-up–free flight–nosing-down. A solution of the terminal problem is to determine numerical values of the control parameters that define moments to switch the RSV flight from one standard trajectory to another.  相似文献   
217.
We consider the peculiarities of application for the cabin indicating systems of secondary information display, formulate and systematize the compositional and technical requirements for display systems and their elements. The tendencies and lines in the development of head-up displays for avionics and autobasing complexes were determined. The technique of calculating optics of such display systems with the use of electronic distortion compensation is presented.  相似文献   
218.
The Relativistic Proton Spectrometer (RPS) on the Radiation Belt Storm Probes spacecraft is a particle spectrometer designed to measure the flux, angular distribution, and energy spectrum of protons from ~60 MeV to ~2000 MeV. RPS will investigate decades-old questions about the inner Van Allen belt proton environment: a nearby region of space that is relatively unexplored because of the hazards of spacecraft operation there and the difficulties in obtaining accurate proton measurements in an intense penetrating background. RPS is designed to provide the accuracy needed to answer questions about the sources and losses of the inner belt protons and to obtain the measurements required for the next-generation models of trapped protons in the magnetosphere. In addition to detailed information for individual protons, RPS features count rates at a 1-second timescale, internal radiation dosimetry, and information about electrostatic discharge events on the RBSP spacecraft that together will provide new information about space environmental hazards in the Earth’s magnetosphere.  相似文献   
219.
柴油发动机热管理系统的高度特性   总被引:1,自引:1,他引:0  
基于空中和高原环境的特点,研究了柴油发动机散热器传热性能的高度特性;进一步建立了发动机热管理系统的流动和传热模型,研究了热管理系统的高度特性;给出了基于最小功耗原则的热管理系统运行参数匹配方法.在固定系统热负荷条件下的计算结果表明:随着海拔高度的增加,在空中环境下,散热器的散热性能先上升后下降,热管理系统中冷却液和润滑油温度先下降后上升,热管理系统所需的最小功耗先减小后增加;在高原环境下,散热器的散热性能随高度增加大幅下降,热管理系统中冷却液和润滑油温度大幅上升,发动机出现过热问题,为了给发动机提供足够的散热能力,热管理系统所需要的最小功耗随着海拔高度的增加而大幅增加.   相似文献   
220.
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