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931.
932.
We present a numerical solution of a Schrödinger equation for three electrons in a quantum dot with hard-wall confining potential in the presence Spin-Orbit coupling. After separation of the problem by some hyperspherical technique, we have solved the resulting equations by using a novel finite difference method. Then a study of the wave functions, eigen-energies and accuracy of the method is done. 相似文献
933.
Anatoly Tur 《Physica D: Nonlinear Phenomena》2011,240(13):1069-1079
In this work we present a new class of exact stationary solutions for two-dimensional (2D) Euler equations. Unlike already known solutions, the new ones contain complex singularities. We consider point singularities which have a vector field index greater than 1 as complex. For example, the dipole singularity is complex because its index is equal to 2. We present in explicit form a large class of exact localized stationary solutions for 2D Euler equations with a singularity whose index is equal to 3. The solutions obtained are expressed in terms of elementary functions. These solutions represent a complex singularity point surrounded by a vortex satellite structure. We also discuss the motion equation of singularities and conditions for singularity point stationarity which provide the stationarity of the complex vortex configuration. 相似文献
934.
Ciprian G. Gal 《Physica D: Nonlinear Phenomena》2011,240(7):629-635
We consider a model for the flow of a mixture of two viscous and incompressible fluids in a two or three dimensional channel-like domain. The model consists of the Navier-Stokes equations governing the fluid velocity coupled with a convective Cahn-Hilliard equation for the relative density of atoms of one of the fluids. We prove the instability of certain stationary solutions for such a system endowed with periodic boundary conditions on elongated domains (0,2π/α0)×(0,2π) or (0,2π/α0)×(0,2π)×(0,2π/β0) for a special class of periodic body forces, provided that α0 and β0 are small enough. As a consequence, we deduce a lower bound for the Hausdorff dimension of the global attractor. 相似文献
935.
The movement of vortices in superconductors due to an applied current can induce a loss of perfect conductivity. Experimental observations show that material impurities can effectively prevent vortices from moving. In this paper, we provide numerical studies to investigate vortex pinning and critical currents through the use of an optimal control approach applied to a variant of the time-dependent Ginzburg-Landau model that can account for normal inclusions. The effects that the size and boundary of the sample and the number, size, shape, orientation, and location of the inclusion sites have on the critical current and vortex lattices are studied. In particular, the optimal control approach is used to determine the optimal properties of the impurities so as to maximize the critical current, i.e., the largest current that can pass through a superconductor without resistance. 相似文献
936.
937.
938.
采用移动粒子半隐式(MPS)方法对静止过冷水中单个汽泡的凝结现象进行了数值模拟,研究了不同初始压力和初始直径时饱和蒸汽汽泡凝结过程,获得了凝结过程中汽泡形状、当量直径和压力的变化规律;汽泡初始压力为0.1~0.5MPa,初始直径为2mm、3mm和5mm;过冷水压力为0.1MPa,温度为70℃。结果表明两相界面不存在压差时,凝结过程中汽泡始终保持球形,汽泡当量直径逐渐减小,压力近似不变;相界面存在压差时,凝结过程中汽泡从球形逐渐变为心形、半月形,汽泡当量直径和压力会出现周期性振荡,且初始压力越大振荡幅度越大。 相似文献
939.
Manwai Yuen 《Physics letters. A》2011,375(44):3821-3825
We construct non-radially symmetry solutions for the compressible 1-dimensional adiabatic Euler equations in this Letter. In detail, we perturb the linear velocity with a drifting term:
(1) 相似文献
940.