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91.
The features of the flowfield and heat transfer on the surface of an axisymmetric body with a narrow groove in its nose immersed
in a hypersonic perfect-gas stream (M∞=6.1) are studied on the basis of a numerical analysis of the two-dimensional Navier-Stokes equations. The calculations are
performed for both thermally insulated and isothermal surfaces having grooves of different width. The calculated results are
compared with experimental data.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 117–124, January–February,
2000.
The study was carried out with the support of the International Scientific and Technical Center (project No. 036). 相似文献
92.
L. E. Vorobjev D. A. Firsov V. A. Shalygin V. Yu. Panevin A. N. Sofronov A. Yu. Egorov V. M. Ustinov A. G. Gladyshev O. V. Bondarenko A. V. Andrianov A. O. Zakhar’in D. V. Kozlov 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(2):212-214
Emission of terahertz radiation from strained Be-doped GaAsN layers has been revealed at 4.2 K in postbreakdown electric fields. Heavy and light hole subbands are split in strained layers, and, along with localized acceptor states, resonant states arise. The spectrum of terahertz radiation has been obtained, the current-voltage characteristics of the samples were investigated, and the energy spectra of acceptors were calculated. Peaks in the spontaneous emission spectrum correlate well with the results of the energy spectrum calculations. The transitions between the resonant and localized states of the acceptors make the main contribution to the terahertz radiation intensity. 相似文献
93.
94.
Transfer mechanisms of the gas dissolved in water are investigated within the framework of the one-dimensional approximation
for a submarine mud volcano. The conditions and intensity of transition of the dissolved gas into the hydrate form inside
the volcano are determined. Practical recommendations on search for hydrate reservoirs in water areas are given. 相似文献
95.
The PESs of systems including deactivated silylenes (SiHHal, SiHal2, Hal = F, Cl, and 2-silaimidazol-2-ylidene, SiN2H2C2H2) and buta-1,3-diene have been studied using G3(MP2)//B3LYP method. Two major reaction channels, (2 + 1) and (4 + 1) cycloaddition reactions, leading to 2-vinylsiliranes and silacyclopent-3-enes, respectively, as well as [1,3]-sigmatropic rearrangements between 2-vinylsiliranes and the corresponding silacyclopent-3-enes, have been considered in detail. Reactivity of silylenes toward buta-1,3-diene decreases in the following series: SiHHal > SiHal2 > SiN2H2C2H2, which is reflected in increase of the reaction barriers for both cycloaddition reactions and in decrease of exothermicity of the formation of the corresponding products. The (4 + 1) cycloaddition is preferable for SiHal2 and SiN2H2C2H2 and can compete with (2 + 1) cycloaddition for SiHHal. [1,3]-Sigmatropic rearrangement is important for isomerization of 2-vinylsiliranes to the corresponding silacyclopent-3-enes for all systems studied, except the SiCl2 system. 相似文献
96.
The paper summarises the validation activity performed with the Scale-Adaptive Simulation turbulence model (SAS model) using
the two commercial CFD solvers, ANSYS-FLUENT and ANSYS-CFX. Both the KSKL-SAS and the SST-SAS model variants have been tested,
although most cases have been computed with the second. The turbulence-resolving capability of the SAS method has been validated
with a representative set of test cases, covering both underlying generic flows as well as practical engineering applications.
In addition to the purely aerodynamic flows with massive separation and heat transfer they include also such physical phenomena
as turbulent combustion and aeroacoustics. The illustrating results show the potentials of the SAS approach for industrial
flow simulations. Most of the test case simulations were conducted during the recent EU project “DESider”. 相似文献
97.
98.
A. L. Antipov A. Yu. Bykovsky N. A. Vasiliev A. A. Egorov 《Bulletin of the Russian Academy of Sciences: Physics》2008,72(5):660-663
Multiple-valued logic functions given by the Allen-Givone algebra are proposed for use in optical nonquantum communication channels as tools for generating a set of secret keys of very high dimension. 相似文献
99.
A unidirectional variation of the pressure applied to Ti-Ni alloy was found to cause strains of different sign when the material
temperature was changed in 10 K steps. The pressure dependence of twin yield stress was obtained. It is concluded that pressure
may initiate twinning in crystals. 相似文献