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11.
In previous studies on plasma-particle interaction, as far as we know, the rf plasma flow and temperature fields are all simulated
by the non-self-consistent one-dimensional electromagnetic (1-D EM) field model. In the present paper, the complete self-consistent
two-dimensional electromagnetic (2-D EM) field model incorporating the axial Lorentz force component, which is neglected in
the 1-D model, is firstly adopted to calculate the aluminium particle trajectory and thermal history in atmospheric rf Ar
plasma with the particle evaporation effect included. The crucial effect of reverse flow within the coil region on the particle
trajectory is discovered and the results show that the 2-D EM field model must be adopted instead of the 1-D model when the
plasma-particle interaction is studied. The effect of carrier gas flux on the particle movement and heating are also studied,
resulting in some useful conclusions for both plasma theory and application.
recommended by Prof. Wu Chengkang
The project supported by the National Natural Science Foundation of China 相似文献
12.
13.
Strain energy density expressions are obtained from a field model that can qualitatively exhibit how the electrical and mechanical disturbances would affect the crack growth behavior in ferroelectric ceramics. Simplification is achieved by considering only three material constants to account for elastic, piezoelectric and dielectric effects. Cross interaction of electric field (or displacement) with mechanical stress (or strain) is identified with the piezoelectric effect; it occurs only when the pole is aligned normal to the crack. Switching of the pole axis by 90° and 180° is examined for possible connection with domain switching. Opposing crack growth behavior can be obtained when the specification of mechanical stress σ∞ and electric field E∞ or (σ∞,E∞) is replaced by strain ε∞ and electric displacement D∞ or (ε∞,D∞). Mixed conditions (σ∞,D∞) and (ε∞,E∞) are also considered. In general, crack growth is found to be larger when compared to that without the application of electric disturbances. This includes both the electric field and displacement. For the eight possible boundary conditions, crack growth retardation is identified only with (Ey∞,σy∞) for negative Ey∞ and (Dy∞,εy∞) for positive Dy∞ while the mechanical conditions σy∞ or εy∞ are not changed. Suitable combinations of the elastic, piezoelectric and dielectric material constants could also be made to suppress crack growth. 相似文献
14.
15.
We prepose a 5-bit lattice Boltzmann model for KdV equation. Using Chapman-Enskog expansion and multiscale technique, we obtained
high order moments of equilibrium distribution function, and the 3rd dispersion coefficient and 4th order viscosity. The parameters
of this scheme can be determined by analysing the energy dissipation.
The project supported by the Foundation of the Laboratory for Nonlinear Mechanics of Continuous Media, Institute of Mechanics,
Chinese Academy of Sciences 相似文献
16.
In this paper, a second-order implicit-explicit upwind algorithm has been developed for three-dimensional Parabolized Navier-Stokes
(PNS) equations. The agreement between the results of the new upwind algorithm and those of the implicit upwind algorithm
and its ability in marching a long distance along the streamwise direction have been shown for the supersonic viscous flow
past a sphere-cone body. The CPU time is greatly reduced.
The project supported by the National Natural Science Foundation of China 相似文献
17.
When the Poisson matrix of Poisson system is non-constant, classical symplectic methods, such as symplectic Runge-Kutta method, generating function method, cannot preserve the Poisson structure. The non-constant Poisson structure was transformed into the symplectic structure by the nonlinear transform.Arbitrary order symplectic method was applied to the transformed Poisson system. The Euler equation of the free rigid body problem was transformed into the symplectic structure and computed by the midpoint scheme. Numerical results show the effectiveness of the nonlinear transform. 相似文献
18.
A finite element-based thermoelastic anisotropic stress model for hexagonal silicon carbide polytype is developed for the
calculation of thermal stresses in SiC crystals grown by the physical vapor transport method. The composite structure of the
growing SiC crystal and graphite lid is considered in the model. The thermal expansion match between the crucible lid and
SiC crystal is studied for the first time. The influence of thermal stress on the dislocation density and crystal quality
is discussed.
The project supported by the National Natural Science Foundation of China (10472126) and the Knowledge Innovation Program
of Chinese Academy of Sciences. The English text was polished by Keren Wang 相似文献
19.
A numerical analysis of flow and concentration fields of macromolecules in a, slightly curved blood vessel was carried out.
Based on these results, the effect of the bifurcation of a flow on the mass transport in a curved blood vessel was discussed.
The macromolecules turned out to be easier to deposit in the inner part of the curved blood vessel near the critical Dean
number. Once the Dean number is higher than the critical number, the bifurcation of the flow appears. This bifurcation can
prevent macromolecules from concentrating in the inner part of the curved blood vessel. This result is helpful for understanding
the possible correlations between the blood dynamics and atherosclerosis.
The project supported by National Natural Science Foundation of China (10002003), JSPS Postdoctoral Fellowship for Foreign
Researcher and Foundation for University Teachers, the Ministry of Education 相似文献
20.
Molecular dynamics (MD) simulations using Morse interaction potential are performed in studies of [110] symmetrical tilt grain
boundary (GB) structures with mis-orientation angles 50.5°(Σ11), 129.5°(Σ11), 70.5°(Σ3) and 109.5°(Σ3) at various tempratures.
The GB structures are found to start local disordering at about 0.5T
m
(T
m
is the melting point of aluminium) for 50.5°(Σ11), 0.32T
m
for 129.5° (Σ11) and 0.38T
m
for 70.5°(Σ3), respectively. These results agree with conclusions deduced from the anelastic measurements. But, for twin-boundary
structure 109.5°(Σ3), this disordering has not been found even when temperature increases up to 0.9T
m
.
The project supported by the National Natural Science Foundation of China and Laboratory for Non-linear Mechanics of Continuous
Media, Institute of Mechanics, Academia Sinica. 相似文献