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941.
Barkhatov N. A. Korolev A. V. Zastenker G. N. Ryazantseva M. O. Dalin P. A. 《Cosmic Research》2003,41(6):529-538
One-dimensional MHD simulations of solitary sharp and strong disturbances (impulses) of the interplanetary magnetic field and plasma of the homogeneous solar wind were performed. The characteristics of a disturbance of this type, recorded onboard the WIND spacecraft (SC) rather far from the Earth, were taken as initial conditions. The results of numerical experiments simulating the evolution of this disturbance in the moving interplanetary plasma, whose parameters correspond to observations of the WIND and INTERBALL-1 SC, show the efficiency of the computer code developed with the special purpose of investigating low-frequency wave events in the space environment. The calculated characteristics of the impulse resulting from the evolution are in good agreement with parameters of the disturbance recorded by the INTERBALL-1 SC closer to the Earth. In particular, the impulse expands due to imbalance of thermal and magnetic pressures, but keeps its abrupt boundaries. It was demonstrated that stable plasma objects, corresponding to stationary MHD solutions, could really exist in the solar wind plasma for a long time. 相似文献
942.
943.
N. Labrosse P. Heinzel J.-C. Vial T. Kucera S. Parenti S. Gunár B. Schmieder G. Kilper 《Space Science Reviews》2010,151(4):243-332
This review paper outlines background information and covers recent advances made via the analysis of spectra and images of
prominence plasma and the increased sophistication of non-LTE (i.e. when there is a departure from Local Thermodynamic Equilibrium) radiative transfer models. We first describe the spectral
inversion techniques that have been used to infer the plasma parameters important for the general properties of the prominence
plasma in both its cool core and the hotter prominence-corona transition region. We also review studies devoted to the observation
of bulk motions of the prominence plasma and to the determination of prominence mass. However, a simple inversion of spectroscopic
data usually fails when the lines become optically thick at certain wavelengths. Therefore, complex non-LTE models become
necessary. We thus present the basics of non-LTE radiative transfer theory and the associated multi-level radiative transfer
problems. The main results of one- and two-dimensional models of the prominences and their fine-structures are presented.
We then discuss the energy balance in various prominence models. Finally, we outline the outstanding observational and theoretical
questions, and the directions for future progress in our understanding of solar prominences. 相似文献
944.
V. N. Pobezhimov 《Russian Aeronautics (Iz VUZ)》2010,53(1):77-80
Problems of the pulsejet flight efficiency dependence on the system parameter periodicity type are considered. 相似文献
945.
I. E. Lobanov 《Russian Aeronautics (Iz VUZ)》2010,53(3):353-357
The analytical solution of a nonlinear nonstationary inverse problem of heat conduction for a bodies with low heat conduction
coefficients of one-dimensional geometry is presented. The solutions obtained make it possible to restore the boundary conditions
rather exactly using the results of heat flux measurements. 相似文献
946.
In this paper, we present the results of calculating conditions for gas vibration excitement, sound pressure frequency and level as a function of mixture composition, geometric burner parameters and the resonator throat with constant capacity. We estimate in quantity the parameters influencing a vibration combustion process in the Helmholtz resonator with the inlet multichannel burner which result in the maximum possible gas vibration amplitude value. 相似文献
947.
Influence of the free air temperature during aircraft takeoff and engine operating time upon the cyclic life of an aircraft
GTE turbine disk made from the heat-resistance deformable nickel-base alloy is analyzed and the variation of engine operating
parameters in the process of service is taken into account. 相似文献
948.
The measurement channel of the air ion counter with impulse signal pickup from the aspiration chamber is considered. Peculiarities
of its functional parts operation are analyzed and restrictions imposed on their parameters are stated. A technique is proposed
and a set of equations that allows determining design parameters of the functional counter parts is presented. 相似文献
949.
A technique and an algorithm for calculating fatigue life of a plate with a concentrator under complex loading in the low-cycle
fatigue region are presented and the life of the plate with different shape concentrators is considered. The local stress
strain state is investigated in the framework of plane loading using the finite element method with the aid of the MSC NASTRAN
software and the life is evaluated with the use of an integral criterion of the concentrator contour loaded-up condition. 相似文献
950.
N. N. Koval’nogov 《Russian Aeronautics (Iz VUZ)》2010,53(3):283-288
The results of design analysis of the different factor influence on the gasodynamic temperature flow stratification efficiency
in the Leont’ev tube are presented. It is justified that the temperature stratification efficiency can be increased at the
expense of using longitudinal ribs on the heat exchange surface in the subsonic flow path, and the parameters determining
the process can be optimized. 相似文献