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271.
V. A. Futin 《Russian Aeronautics (Iz VUZ)》2011,54(2):165-169
The influence of the clearance between the case and blade ends of the semi-open impeller on the centrifugal stage characteristics
is considered using the experimental data and numerical calculation results. 相似文献
272.
The influence of geometry and operating conditions of the centrifugal compressor stage on the radial gas force is determined
on the basis of the theoretical method and calculation program using experimental boundary conditions. 相似文献
273.
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
274.
N. M. Bodunov 《Russian Aeronautics (Iz VUZ)》2011,54(1):89-94
A mathematical model of the process of bending and rolling the thin-walled components is presented taking into account the
geometrical nonlinearity. Also presented is the technique for calculating the setup variables of bending equipment, which
is based on reduction of the initial differential boundary-value problem to the discrete one with the use of the finite difference
method. 相似文献
275.
276.
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
277.
The paper presents a technique of forming and evaluating the allowable clearance between a launch vehicle fairing and spacecraft. 相似文献
278.
M.R. Saradjian M. Hosseini 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
In the past studies, different soil moisture estimation models were developed for bare soil areas by using remotely-sensed data. However, there are few models that can be used to estimate soil moisture in vegetated areas. Water Cloud Model (WCM) model is a widely used soil moisture estimation model has been developed for vegetated areas. In this study, the WCM model was extended to take soil roughness parameter into consideration. The modeling and its accuracy assessment were done by using multi-polarization Airborne Synthetic Aperture Radar (AIRSAR) images and ground data collected during field Soil Moisture Experiments. 相似文献
279.
280.
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