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211.
N. I. Akishev I. I. Zakirov V. A. Ivanov V. N. Paimushin M. A. Shishov 《Russian Aeronautics (Iz VUZ)》2011,54(2):115-124
The known analytical solutions of the linearized stability problems for rectangular hinged plates under the combined loading
are generalized to the similar problems for skew plates, the deformation mechanics of which is described by the equations
of the classical theory formed in the oblique Cartesian coordinates. 相似文献
212.
The basic steps of an algorithm are given for calculating the parameters of the limiting state of a helicopter main rotor
blade. To estimate the static strength, a technique of elastic constants variation is used; it is based on the limit equilibrium
theory and enables us to obtain the upper and lower bounds for the critical load simultaneously. An iterative technique is
proposed to determine the lower bound of the allowable load on the root section of the composite blade depending on the azimuthal
angle of its turn in the helicopter hovering mode. 相似文献
213.
M. V. Usanin A. A. Siner A. M. Sipatov L. Yu. Gomzikov V. G. Avgustinovich 《Russian Aeronautics (Iz VUZ)》2011,54(1):34-42
The application of the low dissipative high-order accurate scheme for numerical solution of the Euler and Navier-Stokes equations
in the two-dimensional statement is considered. The scheme of calculating space derivatives is the seven-point central-difference
approximation of the fourth order with the coefficients optimized to reduce the dispersion errors. The optimized six-step
Runge-Kutta method is used for evaluating the time derivatives. By means of filtration, spurious pulsations are suppressed
and shocks are processed. The results of verifying the calculation scheme realized on the stationary problem of flow around
the model turbine blades are presented. 相似文献
214.
I. Martínez J.M. Perales 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The experimental results obtained in experiment “STACO” made on board the Spacelab D-2 are re-visited, with image-analysis tools not then available. The configuration consisted of a liquid bridge between two solid supporting discs. An expected breakage occurred during the experiment. The recorded images are analysed and the measured behaviour compared with the results of a three dimensional model of the liquid dynamics, obtaining a much better fit than with linear models. 相似文献
215.
The results of the interplanetary scintillation observations performed in the period of the maximum of solar activity from April 2013 to April 2014 on the BSA LPI radio telescope at the frequency 111MHz are presented. Fluctuations of the radio emission flux were recorded round the clock for all sources with a scintillating flux of more than 0.2 Jy falling in a strip of sky with a width of 50° over declinations corresponding to a 96-beam directional pattern of the radio telescope. The total number of sources observed during the day reaches 5000. The processing of the observational data was carried out on the assumption that a set of scintillating sources represents a homogeneous statistical ensemble. Daily two-dimensional maps of the distribution of the level of scintillations, whose analysis shows the strong nonstationarity and large-scale irregularity of the spatial distribution of solar wind parameters, were constructed. According to maps of the distribution of the level of scintillations averaged over monthly intervals, the global structure of the distribution of the solar wind was investigated in the period of the maximum of solar activity, which was found to be on the average close to spherically symmetric. The data show that on a spherically symmetric background an east–west asymmetry is observed, which indicates the presence of a large-scale structure of a spiral type in the solar wind. 相似文献
216.
217.
This paper deals with the technical features of designing an information-controlling system to prevent critical operating conditions of the helicopter flight, a technique for evaluating its effectiveness, analysis and synthesis of the measurement channels, forming of warning signals, and information support of the crew in abnormal situations. 相似文献
218.
We determine the behavior of onboard gas-generator flowrate for generating the cavitation flow around a hybrid aerial underwater vehicle by using an annular wing on the underwater trajectory section. 相似文献
219.
C. J. Hansen M. A. Caplinger A. Ingersoll M. A. Ravine E. Jensen S. Bolton G. Orton 《Space Science Reviews》2017,213(1-4):475-506
Junocam is a wide-angle camera designed to capture the unique polar perspective of Jupiter offered by Juno’s polar orbit. Junocam’s four-color images include the best spatial resolution ever acquired of Jupiter’s cloudtops. Junocam will look for convective clouds and lightning in thunderstorms and derive the heights of the clouds. Junocam will support Juno’s radiometer experiment by identifying any unusual atmospheric conditions such as hotspots. Junocam is on the spacecraft explicitly to reach out to the public and share the excitement of space exploration. The public is an essential part of our virtual team: amateur astronomers will supply ground-based images for use in planning, the public will weigh in on which images to acquire, and the amateur image processing community will help process the data. 相似文献
220.
This paper considers the axisymmetric transverse vibrations of aircraft nonuniform structural elements that are introduced by a thermal shock. Analytical solutions have been obtained and their numerical analysis has been performed. 相似文献