O. A. Zhuravlev  E. V. Shakhmatov  A. N. Kryuchkov  N. D. Bystrov  A. I. Dolgov 《Russian Aeronautics (Iz VUZ)》2009,52(4):463-467

The results of vibration tests for heavy-loaded elements in the auger-centrifugal stage of an aircraft fuel pump performed with the use of an interference-free digital speckle-interferometer created at the Samara State Aerospace University are presented. The speckle-interferograms of an auger and a centrifugal wheel of the auger-centrifugal pump stage in different conditions of attachment and dynamic loading are given. The data obtained may be of sufficient importance in the development of aircraft fuel pumps for a specified service life.  相似文献   

    

V. S. Moiseev  D. S. Gushchina  A. N. Kozar  G. E. Borzov 《Russian Aeronautics (Iz VUZ)》2009,52(3):372-375

We propose a mathematical model and the numerical method for an optimal choice of unmanned aerial vehicles (UAVs) from those being in flight to fulfill a newly received order for monitoring (reconnaissance) of a new region. Examples of using the approach being proposed and main lines of its realization in promising information unmanned aircraft complexes (UAC) are presented.  相似文献   

    

M. S. Ganeeva  V. E. Moiseeva 《Russian Aeronautics (Iz VUZ)》2007,50(4):349-356

A technique for calculating the geometrically and physically nonlinear stress strain state of nonshallow shells of revolution under the nonaxisymmetric wind-like loading is proposed. The calculation results for a semispherical shell with the central hole and rigidly fixed edges depending on the loading nonaxisymmetry, material characteristics and thickness are presented. We demonstrate not only quantitative but also qualitative influence of taking into account the factor of joint nonlinearity on the process of shell deformation.  相似文献   

    

R. P. Lepping  M. H. Acũna  L. F. Burlaga  W. M. Farrell  J. A. Slavin  K. H. Schatten  F. Mariani  N. F. Ness  F. M. Neubauer  Y. C. Whang  J. B. Byrnes  R. S. Kennon  P. V. Panetta  J. Scheifele  E. M. Worley 《Space Science Reviews》1995,71(1-4):207-229

The magnetic field experiment on WIND will provide data for studies of a broad range of scales of structures and fluctuation characteristics of the interplanetary magnetic field throughout the mission, and, where appropriate, relate them to the statics and dynamics of the magnetosphere. The basic instrument of the Magnetic Field Investigation (MFI) is a boom-mounted dual triaxial fluxgate magnetometer and associated electronics. The dual configuration provides redundancy and also permits accurate removal of the dipolar portion of the spacecraft magnetic field. The instrument provides (1) near real-time data at nominally one vector per 92 s as key parameter data for broad dissemination, (2) rapid data at 10.9 vectors s^–1 for standard analysis, and (3) occasionally, snapshot (SS) memory data and Fast Fourier Transform data (FFT), both based on 44 vectors s^–1. These measurements will be precise (0.025%), accurate, ultra-sensitive (0.008 nT/step quantization), and where the sensor noise level is <0.006 nT r.m.s. for 0–10 Hz. The digital processing unit utilizes a 12-bit microprocessor controlled analogue-to-digital converter. The instrument features a very wide dynamic range of measurement capability, from ±4 nT up to ±65 536 nT per axis in eight discrete ranges. (The upper range permits complete testing in the Earth's field.) In the FTT mode power spectral density elements are transmitted to the ground as fast as once every 23 s (high rate), and 2.7 min of SS memory time series data, triggered automatically by pre-set command, requires typically about 5.1 hours for transmission. Standard data products are expected to be the following vector field averages: 0.0227-s (detail data from SS), 0.092 s (detail in standard mode), 3 s, 1 min, and 1 hour, in both GSE and GSM coordinates, as well as the FFT spectral elements. As has been our team's tradition, high instrument reliability is obtained by the use of fully redundant systems and extremely conservative designs. We plan studies of the solar wind: (1) as a collisionless plasma laboratory, at all time scales, macro, meso and micro, but concentrating on the kinetic scale, the highest time resolution of the instrument (=0.022 s), (2) as a consequence of solar energy and mass output, (3) as an external source of plasma that can couple mass, momentum, and energy to the Earth's magnetosphere, and (4) as it is modified as a consequence of its imbedded field interacting with the moon. Since the GEOTAIL Inboard Magnetometer (GIM), which is similar to the MFI instrument, was developed by members of our team, we provide a brief discussion of GIM related science objectives, along with MFI related science goals.  相似文献   

    

E. Silani M. Lovera 《IEEE transactions on aerospace and electronic systems》2006,42(4):1275-1288

A novel approach to the problem of star identification for spacecraft attitude determination based on data provided by a star camera is proposed. The algorithm is based on pattern matching ideas and provides improved reliability with respect to similar methods available in the literature. The achievable performance is demonstrated via a comparison study with two published algorithms  相似文献   

    

Denney  T.S.  Jr. Greene  M.E. 《IEEE transactions on aerospace and electronic systems》1991,27(4):689-695

The effects of instrumentation accuracy and configuration on estimation error are studied for the small expandable-tether deployment system (SEDS) using a continuous-discrete extended Kalman filter (CDEKF) state estimator. A twelfth order model that incorporates the rigid body modes of the tether as well as the satellite attitude dynamics is developed. Simulation results using the model and the estimator indicate that the originally planned instrumentation package could not estimate the state vector adequately. Recommendations are made and results presented that reduce the estimation error by adding instruments and increasing selected measurement accuracies  相似文献   

    

A.?V.?Gorelov  "mailto:a.gorelov-kai@yandex.ru  " title=  "a.gorelov-kai@yandex.ru  " itemprop=  "email  " data-track=  "click  " data-track-action=  "Email author  " data-track-label=  "  ">Email author  E.?I.?Nikolaev  I.?N.?Sidorov 《Russian Aeronautics (Iz VUZ)》2016,59(3):308-315

Safety factors of the Ansat helicopter main rotor blade are determined in the root section at various flight modes with taking into account the possible damages.  相似文献   

    

E. G. Podruzhin  A. R. Zagidulin 《Russian Aeronautics (Iz VUZ)》2017,60(3):342-348

The paper describes a mathematical model of drop tests on the landing gear of the Ka-62 helicopter. The model is formulated using the multibody system simulation procedure based on the Lagrange equations of the first kind.  相似文献   

    

M. B. Kraev  E. M. Kraeva 《Russian Aeronautics (Iz VUZ)》2013,56(2):166-171

In this paper, some features of cavity development are presented for a case of a flow around the blade profile of the centrifugal pump impeller. Based on the photographs obtained in visualization of the cavitation centrifugal pump operation conditions, we refined the shape, volumes, and parameters of cavity growth in the centrifugal pump flow passage. Also presented are the relations characterizing the features of cavity formation in the centrifugal force field.  相似文献   

    

Brennan  Lawrence E. Reed  Irving S. 《IEEE transactions on aerospace and electronic systems》1968,(3):474-477

A train of radar pulses from one resolution cell can be processed coherently to reject echoes from external clutter and detect targets moving radially with respect to the clutter. Optimum methods of signal processing are defined for systems in which the interpulse spacings are multiply staggered to avoid target blind speeds. Likelihood ratio tests are developed for systems in which the target Doppler frequency is known a priori and for systems employing a bank of filters to cover the target Doppler band. To implement such tests, the N pulses in the train are added with complex weights and the amplitude of the sum compared with a detection threshold. The set of weights which maximizes the average signal-to-clutter ratio is also computed for a single-filter system with unknown target Doppler frequency. When the clutter autocorrelation function is exponential, the clutter covariance matrix can be inverted analytically. This latter result is useful for comparing different interpulse-spacing codes for a particular system application.  相似文献