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1.
Variations in the positions of the intersection points of tangents to ray structures in the polar corona of the Sun during the solar cycle are considered. At first glance, the decrease in the distance q between the tangent intersection point and the center of the solar disk during activity maximum contradicts harmonic analyses that indicate that the relative weight of higher harmonics in the global field increases during this period. Indeed, the higher the harmonic number in an axisymmetric field, the closer the intersection point of the field-line tangents (the magnetic focus) to the solar surface. It is shown that q for a field composed of two harmonics with opposite polarities at the poles can be smaller than q for either of them taken alone. A simple model representing the global field using the third and seventh harmonics is analyzed; this model can reproduce quite satisfactorily the observed dynamics of magnetic foci of the polar field. 相似文献
2.
The kinematics of the material motion in a variable magnetic field in the MHD approximation of a strong field and cold plasma is investigated. The variation of magnetic moments of two dipole systems leads to the development of such phenomena as loop prominences, coronal rain and funnel prominences. 相似文献
3.
N. Krupchatnikov G. A. Platov E. N. Golubeva A. A. Fomenko Yu. Yu. Klevtsova V. N. Lykosov 《Russian Meteorology and Hydrology》2018,43(11):713-721
The results of studies in the area ofnumerical weather prediction and climate theory are presented. These results were obtained by the team of researchers of the Siberian school of mathematical modeling of atmosphere and ocean dynamics established by academician G.I. Marchuk. Academician V.P. Dymnikov played an enormous role in the development of this school by enriching it with new approaches and ideas. His contribution to the Siberian school of mathematical modeling was most strongly pronounced concerning three problems: numerical weather prediction for the Siberian region, the modeling of the climate system dynamics, and the mathematics and theory of climate. 相似文献
4.
Condensation of water vapor and carbon dioxide in the jet exhausts of rocket engines during last stages of Proton, Molniya, and Start launchers operating in the upper atmospheric with different types of fuels is considered. Particle heating is taken into account with emission of latent heat of condensation and energy loss due to radiation and heat exchange with combustion products. Using the solution of the heat balance and condensed particle mass equations, the temporal change in the temperature and thickness of the condensate layer is obtained. Practically, no condensation of water vapor and carbon dioxide in the jet exhaust of a Start launcher occurs. In plumes of Proton and Molniya launchers, the condensation of water vapor and carbon dioxide can start at distances of 120–170 m and 450–650 m from the engine nozzle, respectively. In the course of condensation, the thickness of the “water” layer on particles can exceed 100 Å, and the thickness of carbon dioxide can exceed 60 Å. 相似文献
5.
The condensation process of water vapors in the exhaust plume of a rocket engine in the upper atmosphere is considered. We take into account the processes of particle heating during the release of latent heat of condensation, radiative heating, and energy losses to emission. From the solution of the equations of thermal balance and mass balance of condensing particles, we obtained the time dependences of variations in temperature and particle sizes. In the process of condensation, the thickness of the ice layer on particles may reach >70 Å. 相似文献
6.
The dispersion of exhaust products of rocket fuel in the direction perpendicular to the motion of a rocket is investigated
in this work. A comparison of the results of numerical calculations with a self-similar approximation of a strong cylindrically
symmetric explosion is fulfilled. It is shown that at sufficiently high rocket velocity V
∞, which exceeds the sum of gas exhaust velocity V
e
from the nozzle and sound speed V
s
(V
∞ > V
e
+V
s
), a gasdynamic hole can arise around the rocket trajectory in the upper atmosphere, inside which the total concentration
of gas becomes less than the equilibrium concentration of gas at a given altitude. The dynamics of the profiles of density
and temperature of the exhaust products inside a rocket plume is calculated. 相似文献
7.
In this study, the hydrological characteristics of water in the Japan Sea are considered on the basis of the GDEM data of climatic distribution of temperature and salinity [1]. Using a regional-scale numerical model, we investigate the dynamics of these waters and perform a detailed analysis of the formation and propagation of intermediate waters in the Japan Sea. On the basis of numerical modeling, we reveal that the process of the formation and propagation of intermediate waters can be separated into three stages. The first stage is related to the accumulation of a significant water reserve with properties close to the type of intermediate waters in the vicinity of Peter the Great Bay. The second stage involves the penetration of these waters into intermediate layers as a result of deep convection in the presence of a winter monsoon. The third stage occurs for a reduced subpolar front and leads to the propagation of intermediate waters southward to the Ulung and Yamato basins as well as to their partial recirculation within the northern gyre. 相似文献
8.
G. A. Platov 《Izvestiya Atmospheric and Oceanic Physics》2011,47(3):362-376
In this study the capability of numerical models to transport anomalously dense bottom waters from the areas of their generation on the shelf to deepwater areas is considered. These numerical models have a number of mechanisms that are favorable for this transport, but unrelated directly with the real physics of that motion. A more accurate account of the resupply of oceanic deep waters requires either a very fine resolution for the numerical model or an efficient parametrization. Two such parametrizations are proposed in this study. The first is based on amplified lateral diffusion exchange if slope instability exists. The second is related to an additional procedure allowing dense waters to leak under waters of lesser density along a shelf slope with their displacement to higher layers. The first parametrization is shown to be less efficient because it leads to a significant interaction between anomaly waters and ambient waters and to a quick loss of their original features. The second procedure is more preferable because it leads to a significant resupply of dense deep waters at the expense of dense waters generated at a distance significantly far from the shelf break. With the help of the given parametrization, during a numerical experiment these waters can be transported considerable distances away from their place of generation to the shelf boundary and deepwater areas of the ocean with a slight change in their original density characteristics. 相似文献
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10.
Geomagnetism and Aeronomy - Photographic and video observations made by astronaut Thomas Pesquet (European Space Agency) during the 51st expedition to the International Space Station (ISS) contain... 相似文献