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311.
An algorithm of analyzing the design parameters for a thin-walled wing from composite material based on the efficient distribution
of structural material between load-carrying elements is described. We consider the problems of convergence acceleration for
the iteration design analysis. Also presented are the examples of determining the design parameters for a superlight aircraft
wing and the rational parameters of the filler in the form of a three-dimensional rod structure. 相似文献
312.
We considered the influence of temperature on the nitric oxide emission under combustion of the near-stoichiometric mixtures
with and without water feed. We revealed the advantage of the method of fuel-water-air mixture combustion over that of the
leaned mixture combustion. 相似文献
313.
Systems for the indication and display of secondary information in avionics and autobasing complexes
A. A. Bagdasarov R. V. Anitropov O. V. Bagdasarova I. L. Livshits 《Russian Aeronautics (Iz VUZ)》2011,54(2):185-191
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
314.
Aerodynamic characteristics of two-dimensional smart flap under the ground effect have been assessed by a numerical simulation. In this process, a pressure-based implicit procedure to solve Navier–Stokes equations on a nonorthogonal mesh with collocated finite volume formulation is used. The boundedness criteria for this procedure are determined from the Normalized Variable Diagram (NVD) scheme. The procedure incorporates the k–ε eddy–viscosity turbulence model. Cantilever beam with uniformly varying load with roller support at the free end is considered for the configuration of the smart flap. The method is first validated against experimental data. Then, the algorithm is applied for turbulent aerodynamic flows around airfoil with smart and conventional flaps for different attack angle, flap angle and ground clearance where the results of two flaps are compared. The comparisons show that the quality of the solution is considerable. 相似文献
315.
H.S. Ahluwalia J. Jackiewicz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
The decay phase of the sunspot cycle 23 exhibited two unusual features. First, it lasted too long. Second, the interplanetary magnetic field intensity at earth orbit reached the lowest value since in situ measurements in space began in October 1963. These physical anomalies significantly altered the early forecasts for the sunspot activity parameters for cycle 24, made by several colleagues. We note that there was a significant change in the solar behavior during cycle 22. We discuss the observed trends and their effect on our empirical solar activity forecast technique, leading to our prediction for cycle 24 parameters; cycle 24 will be only half as active as cycle 23, reaching its peak in May 2013. We speculate on the possible implications of this outcome on future earth climate change and the ensuing socio-economic consequences. 相似文献
316.
J. Mazur L. Friesen A. Lin D. Mabry N. Katz Y. Dotan J. George J. B. Blake M. Looper M. Redding T. P. O’Brien J. Cha A. Birkitt P. Carranza M. Lalic F. Fuentes R. Galvan M. McNab 《Space Science Reviews》2013,179(1-4):221-261
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
317.
R.?A.?KayumovEmail author I.?Z.?Mukhamedova E.?B.?Tuisina 《Russian Aeronautics (Iz VUZ)》2016,59(4):452-459
This paper considers a beam with a technological longitudinal section on the level of the gravity center of the cross section that is loaded by a vertical concentrated force. We study the structure durability depending on the load amplitude and the initial crack length. 相似文献
318.
319.
This paper investigates the dynamics and de-spin control of a massive target by a single tethered space tug in the post-capture phase. The dynamic model of the tethered system is derived and simplified to a dimensionless form. Further, a decoupled PD controller is proposed, and the local stability of the controller is analyzed by linearization technique. Parametric studies of the dynamics and de-spin control of a massive target are conducted to characterize the dynamic process of de-spin with the proposed control law. It is shown that the massive target can be de-span by a single and small space tug with limited thrust within finite time. The thrust tangent with the tether de-spins the target while the thrust normal to the tether prevents the tether from winding up the target. The tether length has a positive contribution to the de-spin of a target. The longer tether leads to a faster de-spin process. 相似文献
320.
The Electric Antennas for the STEREO/WAVES Experiment 总被引:1,自引:0,他引:1
S. D. Bale R. Ullrich K. Goetz N. Alster B. Cecconi M. Dekkali N. R. Lingner W. Macher R. E. Manning J. McCauley S. J. Monson T. H. Oswald M. Pulupa 《Space Science Reviews》2008,136(1-4):529-547
The STEREO/WAVES experiment is designed to measure the electric component of radio emission from interplanetary radio bursts and in situ plasma waves and fluctuations in the solar wind. Interplanetary radio bursts are generated from electron beams at interplanetary shocks and solar flares and are observed from near the Sun to 1 AU, corresponding to frequencies of approximately 16 MHz to 10 kHz. In situ plasma waves occur in a range of wavelengths larger than the Debye length in the solar wind plasma λ D ≈10 m and appear Doppler-shifted into the frequency regime down to a fraction of a Hertz. These phenomena are measured by STEREO/WAVES with a set of three orthogonal electric monopole antennas. This paper describes the electrical and mechanical design of the antenna system and discusses efforts to model the antenna pattern and response and methods for in-flight calibration. 相似文献