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Summary The nonlinear differential equations describing the problem of shock wave structure in a two-component gas mixture are reduced
to a system of two coupled nonlinear differential equations. This system is solved numerically using the finite-difference
method. It is found that the relative shock wave thickness of the mixture increases with the increase of the ratio between
the viscosity coefficients when the ratio between the mass fractions is constant. It is also shown that the relative shock
wave thickness of the mixture decreases with the increase of the ratio between the mass fractions when the ratio between the
viscosity coefficients is constant.
Riassunto Si riducono le equazioni differenziali non lineari che descrivono il problema della struttura dell’ onda d’urto in una miscela di gas a 2 componenti a un sistema di due equazioni differenziali accoppiate non lineari. Questo sistema si risolve numericamente usando il metodo delle differenze finite. Si trova che il relativo spessore dell’onda d’urto della miscela aumenta con l’aumento del rapporto tra i coefficienti di viscosità, quando il rapporto tra le frazioni di massa è costante. Si mostra anche che lo spessore relativo dell’onda d’urto della miscela diminuisce con l’aumento del rapporto tra le frazioni della massa, quando il rapporto tra i coefficienti di viscosità è costante.
Резюме Нелинейные дифференциальные уравнения, описывающие проблему структуры ударной в двух-компоентной газовой смеси, сводятся к системе двух связанных нелинейыых дифференциальных уравнений. Получается, что относительная толщина ударной волны в смеси увеличвается с увеличением отношения между коэффиыентами вязкоти, когда отнощение между массовыми доями остается постоянным. Также показывается. что относительная толщина ударной волны уменьшается с увеличением отношения между массовыми долями. когда отношение между коэффициентами вязкости остается постоянным.相似文献
105.
AA Yan LI Kai CAO ZhongHua & HU WenRui Key Laboratory of Microgravity 《中国科学:物理学 力学 天文学(英文版)》2011,(2)
The dependency of the critical Marangoni number on the geometrical aspect ratio of the floating half zone is essential to predict the onset of oscillatory thermocapillary convection.The experimental studies in the microgravity conditions on floating half zones of several centimeters in diameter have predicted that the critical Marangoni number increases with the increasing aspect ratio,and the terrestrial experimental studies have predicted the contradictory conclusion for floating half zones of several mil... 相似文献
106.
The (1+1)-dimensional Duffin-Kemmer-Petiau (DKP) equation (for spin 0 and 1) in the Robertson-Walker Space-time is solved.
The exact solution is then determined for both cases. As an application, the rate of the created particles in the presence
of gravity is calculated via the Bogoliubov transformations technique. 相似文献
107.
NaAgPbP2O7 was prepared with a solid-state reaction. The electrical properties were investigated by using impedance measurements in
the frequency range from 200 Hz to 5 MHz with the TEGAM 3550 ALF automatic bridge monitored by a microcomputer between 581 K
and 703 K. The Z′ and Z″ versus frequency plots are well fitted to an equivalent circuit model. The conductivity data obey the universal power law.
The conductivity in the material is due to the hopping of monovalent ions parallel to (001) plane. 相似文献
108.
Karem B. Ben Mahmoud 《Numerical Methods for Partial Differential Equations》2009,25(4):802-809
In this article, a new set of polynomials is proposed as a new tool for solving bivaried partial differential equation related with some appropriated applied physics problems. A concrete formulation of canonical expressions, with respect to more common boundary conditions, is yielded out of the recently established Boubaker polynomials. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009 相似文献
109.
Mohamed Rafat Mahmoud Maher Mohamed Ahmed Hamed Ali Mohamed Shaker 《Journal of solution chemistry》1986,15(9):765-776
Kinetics of base hydrolysis of new heterocyclic azomethines derived from active methyl quaternary salts and aromatic nitroso compounds were investigated in the presence of 70% (wt/wt) water-methanol. The base hydrolysis of these compounds is strictly first-order with respect to OH– and azomethine. The rate determining step is suggested to be the attack of the hydroxide ion on the free base. Effects of water content and nature of organic hydroxylic solvent have been studied. It is concluded that specific solute-solvent interactions through dispersion forces play a major role in the base hydrolysis rate of the azomethines investigated. The effect of pH (2.98 – 12.24) on hydrolysis rates of compounds having a diethylamino substituent in the presence of 30% methanol has been studied. In acidic media, the rate determining step is probably the water attack on the protonated substrate. 相似文献
110.