Dynamic failure and ejection characteristics of a periodic grooved Sn surface under unsupported shock loading are studied using a smoothed particle hydrodynamics method. An ＂Eiffel Tower＂ spatial structure is observ...
详细信息
Dynamic failure and ejection characteristics of a periodic grooved Sn surface under unsupported shock loading are studied using a smoothed particle hydrodynamics method. An ＂Eiffel Tower＂ spatial structure is observed, which is com- posed of high-speed jet tip, high-density jet slug, longitudinal tensile sparse zone, and complex broken zone between grooves. It is very different from the spike-bubble structure under supported shocks, and has been validated by detonation loading experiments. In comparison with that under supported shocks at the same peak pressure, the high-speed ejecta decreases obviously, whereas the truncated location of ejecta moves towards the interior of the sample and the total mass of ejecta increases due to the vast existence of low-speed broken materials. The shock wave profile determines mainly the total ejection amount, while the variation of V-groove angle will significantly alter the distribution of middle- and high-speed ejecta, and the maximum ejecta velocity has a linear corretation with the groove angle.
We investigate the dynamics of two interacting electrons confined in a quantum dot molecule under the influence of cosine squared electric fields. The conditions for two-electron localization in the same quantum dot a...
详细信息
We investigate the dynamics of two interacting electrons confined in a quantum dot molecule under the influence of cosine squared electric fields. The conditions for two-electron localization in the same quantum dot are analytically derived within the frame of the Floquet formalism. The analytical results are compared to numerical results obtained from the solution of the time-dependent Schtdinger equation.
The effects of a premixed layer on the Richmyer–Meshkov instability(RMI)are studied by setting a density gradient for the first shocked fluid in the RMI *** RMI with initial density gradients are simulated by using a...
详细信息
The effects of a premixed layer on the Richmyer–Meshkov instability(RMI)are studied by setting a density gradient for the first shocked fluid in the RMI *** RMI with initial density gradients are simulated by using a high resolution arbitrary Lagrangian–Eulerian *** effects of density gradient and gradient width are analyzed on the basis of the simulation results for the shock from a light fluid to a heavy fluid and for the shock from a heavy fluid to a light ***,the premixed layer can suppress the perturbation growth,and the detailed effects are different depending on the detailed premixed *** width of the premixed layer has a very light influence on the perturbation,while the density gradient has quite a significant effect on two kinds of RMIs.
Stimulated Raman particle-in-cell （PIC） simulations scattering （SRS） in a low-density The backward stimulated Raman plasma slab is investigated by scattering （B-SRS） dominates initially and erodes the head of th...
详细信息
Stimulated Raman particle-in-cell （PIC） simulations scattering （SRS） in a low-density The backward stimulated Raman plasma slab is investigated by scattering （B-SRS） dominates initially and erodes the head of the pump wave, while the forward stimulated Raman scattering （F-SRS） subsequently develops and is located at the rear part of the slab. Two-stage electron acceleration may be more efficient due to the coexistence of these two instabilities. The B-SRS plasma wave with low phase velocities can accelerate the background electrons which may be further boosted to higher energies by the F-SRS plasma wave with high phase velocities. The simulations show that the peaks of the main components in both the frequency and wave number spectra occur at the positions estimated from the phase-matching conditions.
Fast multipole method (FMM) may reduce the complexity of N-body problems from O(N 2 ) to O(N log N) or O(N).It was applied in problems ranging from electromagnetic scattering to dislocation *** can be divided into two...
详细信息
Fast multipole method (FMM) may reduce the complexity of N-body problems from O(N 2 ) to O(N log N) or O(N).It was applied in problems ranging from electromagnetic scattering to dislocation *** can be divided into two parts: commonness and individuality.A parallel solver of FMM commonly used in various applications has been designed and implemented in JASMIN *** solver encapsulates the ***,it supplies users with abstract interfaces required to implement the individuality with serial *** commonness contains distributed storage of multi-levels,intra-level and inter-level data communication,and arrangement of computation,*** individuality contains various expansion and translation *** give here two applications that have used the *** was demonstrated with a parallel efficiency above 80% on 1024 processors.
Effect of electron-ion collision on stimulated Raman backward scattering （SRBS） spectrum are investigated by numerical simulations. In the given parameters and plasma condition, the growth rates of SRBS are found to...
详细信息
Effect of electron-ion collision on stimulated Raman backward scattering （SRBS） spectrum are investigated by numerical simulations. In the given parameters and plasma condition, the growth rates of SRBS are found to strongly depend on the electron density, and the gap in the SRBS spectrum corresponding to the high electron density could be explained by the collisional damping. In the low density region, a much higher Landau damping estimated by the linear theory makes the collisional damping negligible. However, the present results show that, collisions play a even more important role than known in the linear theory.
This paper investigates the electron-vibrational（e-V）energy exchange in nitrogencontaining plasma,which is very efficient in the case of gas discharge and high speed *** on Harmonic oscillator approximation and the ...
详细信息
This paper investigates the electron-vibrational（e-V）energy exchange in nitrogencontaining plasma,which is very efficient in the case of gas discharge and high speed *** on Harmonic oscillator approximation and the assumption of the e-V relaxation through a continuous series of Boltzmann distributions over the vibrational states,an analytic approach is derived from the proposed scaling relation of e-V transition rates.A full kinetic model is then investigated by numerically solving the state-to-state master equation for all vibrational *** analytical approach leads to a Landau-Teller（LT）-type equation for relaxation of vibrational energy,and predicts the relaxation time on the right order of *** comparison with the kinetic model,the LT-type equation is valid in typical electron temperatures in gas ***,the analytical approach is not capable of describing the vibrational distribution function during the e-V process in which a full kinetic model is required.
A theoretical scheme is derived to achieve the numerical simulation of helical flux compression generator （HFCG） design, by which not only any physical approximation is not made, but also numerical simulation can be...
详细信息
A theoretical scheme is derived to achieve the numerical simulation of helical flux compression generator （HFCG） design, by which not only any physical approximation is not made, but also numerical simulation can be fast obtained. In particular, an analytic formula to calculate the inductance is deduced, which is extremely close to the experimental results. The physical process of relevant interesting physical quantity, such as inductance, enlarging current, and magnetic flux density, can be calculated to compare with the experimentally quantitative results.
In this paper,a six-cylinder-port hohlraum is proposed to provide high symmetry flux on *** is designed to ignite a capsule with 1.2-mm radius in indirect-drive inertial confinement fusion（ICF）.Flux symmetry and las...
详细信息
In this paper,a six-cylinder-port hohlraum is proposed to provide high symmetry flux on *** is designed to ignite a capsule with 1.2-mm radius in indirect-drive inertial confinement fusion（ICF）.Flux symmetry and laser energy are calculated by using three-dimensional view factor method and laser energy balance in *** conditions are analyzed based on the two-dimensional radiation-hydrodynamic *** is no Y_（lm）（l≤4） asymmetry in the six-cylinder-port hohlraum when the influences of laser entrance holes（LEHs） and laser spots cancel each other out with suitable target parameters.A radiation drive with 300 eV and good flux symmetry can be achieved by using a laser energy of 2.3 MJ and peak power of 500 *** to the simulations,the electron temperature and the electron density on the wall of laser cone are high and low,respectively,which are similar to those of outer cones in the hohlraums on National Ignition Facility（NTF）.And the laser intensity is also as low as those of NIF outer *** the backscattering due to laser plasma interaction（LPI） is considered to be *** six-cyliner-port hohlraum could be superior to the traditional cylindrical hohlraum and the octahedral hohlraum in both higher symmetry and lower backscattering without supplementary technology at an acceptable laser energy *** is undoubted that the hohlraum will add to the diversity of ICF approaches.
In this paper, we investigate the dynamical instability of the dark state in the conversion of Bose-Fermi mixtures into stable molecules through a stimulated Raman adiabatic passage aided by Feshbach resonance. We ana...
详细信息
In this paper, we investigate the dynamical instability of the dark state in the conversion of Bose-Fermi mixtures into stable molecules through a stimulated Raman adiabatic passage aided by Feshbach resonance. We analytically obtain the regions where the dynamical instability appears and find that such instability in the Bose-Fermi mixture system is caused not only by bosonic interparticle interactions but also by Pauli blocking terms, which is different from the scenario of a pure bosonic system where instability is induced by nonlinear interparticle collisions. Taking a 40K-87Rb mixture as an example, we give the unstable regions numerically.
暂无评论