检索结果-南通市图书馆

High-Order Semi-Lagrangian WENO Schemes Based on Non-polynomial Space for the vlasov equation

在线全文

学校读者我要写书评

暂无评论

Communications on Applied Mathematics and Computation 2023年第1期5卷 116-142页

作者： Andrew Christlieb Matthew Link Hyoseon Yang Ruimeng Chang Department of Computational Mathematics Science and EngineeringMichigan State UniversityEast LansingMI 48824USA Department of Mathematical Sciences Xi'an Jiaotong-Liverpool UniversitySuzhou 215123JiangsuChina

In this paper,we present a semi-Lagrangian(SL)method based on a non-polynomial function space for solving the vlasov *** fnd that a non-polynomial function based scheme is suitable to the specifcs of the target *** address issues that arise in phase space models of plasma problems,we develop a weighted essentially non-oscillatory(WENO)scheme using trigonometric *** particular,the non-polynomial WENO method is able to achieve improved accuracy near sharp gradients or ***,to obtain a high-order of accuracy in not only space but also time,it is proposed to apply a high-order splitting scheme in *** aim to introduce the entire SL algorithm with high-order splitting in time and high-order WENO reconstruction in space to solve the vlasov-Poisson *** numerical experiments are presented to demonstrate robustness of the proposed method in having a high-order of convergence and in capturing non-smooth solutions.A key observation is that the method can capture phase structure that require twice the resolution with a polynomial based *** 6D,this would represent a signifcant savings.

关键词： Semi-Lagrangian methods WENO schemes High-order splitting methods Non-polynomial basis vlasov equation vlasov-Poisson system

Conservative Semi-Lagrangian Finite Difference WENO Formulations with Applications to the vlasov equation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Computational Physics 2011年第9期10卷 979-1000页

作者： Jing-Mei Qiu Chi-Wang Shu Department of Mathematical and Computer Science Colorado School of MinesGoldenCO 80401USA Division of Applied Mathematics Brown UniversityProvidenceRI 02912USA

In this paper,we propose a new conservative semi-Lagrangian(SL)finite difference(FD)WENO scheme for linear advection equations,which can serve as a base scheme for the vlasov equation by Strang splitting[4].The reconstruction procedure in the proposed SL FD scheme is the same as the one used in the SL finite volume(FV)WENO scheme[3].However,instead of inputting cell averages and approximate the integral form of the equation in a FV scheme,we input point values and approximate the differential form of equation in a FD spirit,yet retaining very high order(fifth order in our experiment)spatial *** advantage of using point values,rather than cell averages,is to avoid the second order spatial error,due to the shearing in velocity(v)and electrical field(E)over a cell when performing the Strang splitting to the vlasov *** a result,the proposed scheme has very high spatial accuracy,compared with second order spatial accuracy for Strang split SL FV scheme for solving the vlasov-Poisson(VP)*** perform numerical experiments on linear advection,rigid body rotation problem;and on the Landau damping and two-stream instabilities by solving the VP *** comparison,we also apply(1)the conservative SL FD WENO scheme,proposed in[22]for incompressible advection problem,(2)the conservative SL FD WENO scheme proposed in[21]and(3)the non-conservative version of the SL FD WENO scheme in[3]to the same test *** performances of different schemes are compared by the error table,solution resolution of sharp interface,and by tracking the conservation of physical norms,energies and entropies,which should be physically preserved.

关键词： Semi-Lagrangian methods finite difference/finite volume scheme conservative scheme WENO reconstruction vlasov equation Landau damping two-stream instability

Landau damping in a bounded magnetized plasma column

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2015年第2期24卷 287-294页

作者： H.Zakeri-Khatir F.M.Aghamir Department of Physics University of Tehran

The damping decrement of Landau damping and the effect of thermal velocity on the frequency spectrum of a propagating wave in a bounded plasma column are *** magnetized plasma column partially filling a cylindrical metallic tube is considered to be collisionless and *** Landau damping is due to the thermal motion of charge carriers and appears whenever the phase velocity of the plasma waves exceeds the thermal velocity of *** analysis is based on a self-consistent kinetic theory and the solutions of the wave equation in a cylindrical plasma waveguide are presented using vlasov and Maxwell *** hybrid mode dispersion equation for the cylindrical plasma waveguide is obtained through the application of appropriate boundary conditions to the plasma-vacuum *** dependence of Landau damping on plasma parameters and the effects of the metallic tube boundary on the dispersion characteristics of plasma and waveguide modes are investigated in detail through numerical calculations.

关键词： Landau damping cylindrical plasma waveguide vlasov equation dispersion characteristic

A fast convergence fourth-order vlasov model for Hall thruster ionization oscillation analyses

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2022年第2期24卷 117-126页

作者： Zhexu WANG Rei KAWASHIMA Kimiya KOMURASAKI Univ Tokyo Bunkyo Ku 7-3-1 Hongo Tokyo 1138656 Japan

A 1D1 V hybrid vlasov-fluid model was developed for this study to elucidate discharge current oscillations of Hall thrusters(HTs).The vlasov equation for ions velocity distribution function with ionization source term is solved using a constrained interpolation profile conservative semiLagrangian *** fourth-order weighted essentially non-oscillatory(4 th WENO)limiter is applied to the first derivative value to minimize numerical oscillation in the discharge oscillation *** fourth-order accuracy is verified through a 1 D scalar test *** and high-resolution features of the vlasov model are confirmed by simulating the test cases of the vlasov–Poisson system and by comparing the results with a particle-in-cell(PIC)method.A1 D1 V HT simulation is performed through the hybrid vlasov *** ionization oscillation is *** oscillation amplitude and plasma density are compared with those obtained from a hybrid PIC *** comparison indicates that the hybrid vlasov-fluid model yields noiseless results and that the steady-state waveform is calculable in a short time period.

关键词： Hall thruster ionization oscillation vlasov equation semi-Lagrangian method

Theoretical investigation of a backward wave oscillator

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2008年第4期32卷 290-293页

作者：马乔生周传明吴勇 Institute of Applied Electronics China Academy of Engineering Physics

From the linear vlasov equation, the theoretical investigation on relativistic backward wave oscillator is performed. The relationship between the microwave power and the guiding magnetic field, which accords with the... 详细信息

关键词： microwave guiding magnetic field vlasov equation backward wave oscillator

A Coulomb explosion theoretical model of femtosecond laser ablation materials

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2012年第3期55卷 694-701页

作者： LIN XiaoHui CHEN HaiQuan JIANG ShuYun ZHANG ChiBin Department of Mechanical Engineering Southeast UniversityNanjing 210096China

In this paper,a kinetic theory of vlasov equation is proposed to depict electron and ion's nonequilibrium transport processes in a femtosecond time scale.A Coulomb explosion model of femtosecond laser ablation of materials is proposed and numerically *** mechanism of surface Coulomb explosion induced by self-consisted electric field and the impact of laser parameters on the ablation of materials are quantitatively *** ablation depths calculated by the model are in good agreement with the experimental *** is shown that,the intensity of self-consisted electric field generated on the dielectric material's surface is much greater than that generated on the metal or the semiconductor material's surface,and Coulomb explosion ablation is more easily to occur on the dielectric material's surface.

关键词： femtosecond laser Coulomb explosion surface ablation vlasov equation

Direct vlasov Solvers with High-Order Spectral Element Method

在线全文

学校读者我要写书评

暂无评论

Communications in Computational Physics 2010年第6期8卷 159-184页

作者： Jin Xu Brahim Mustapha Peter Ostroumov Jerry Nolen Physics Division Argonne National Laboratory9700 S.Cass Ave.ArgonneIL 60439USA Mathematics and Computer Science Division Argonne National Laboratory9700 S.Cass Ave.ArgonneIL 60439USA

This paper presents the development of parallel direct vlasov solvers using the Spectral Element Method(SEM).Instead of the standard Particle-In-Cell(PIC)approach for kinetic space plasma simulation,*** the vlasov-Maxwell equations,the direct method has been used in this *** are several benefits to solve the vlasov equation directly,such as avoiding noise associated with the finite number of particles and the capability to capture the fine structure in the plasma,*** most challenging part of direct vlasov solver comes from high dimension,as the computational cost increases as N2d,where d is the dimension of the physical *** due to fast development of supercomputers,the possibility of high dimensions becomes more realistic.A significant effort has been devoted to solve the vlasov equation in low dimensions so far,now more interests focus on higher *** numerical methods have been tried so far,such as finite difference method,Fourier spectral method,finite volume method,*** this paper SEM has been successfully applied to construct these *** has shown several advantages,such as easy interpolation due to local element structure and long time integration due to its high order *** decomposition in high dimensions have been used for parallelization,these include scalable parallel 1D and 2D Poisson *** results have been shown and simulation results have been reported for two different cases:one dimension(1P1V),and two dimensions(2P2V)in both physical and velocity spaces.

关键词： vlasov equation Spectral Element Method Poisson’s equation interpolation domain decomposition

An Accurate Numerical Scheme for Maxwell equation with CIP-Method of Characteristics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Computational Physics 2006年第2期1卷 311-335页

作者： Youichi Ogata Takashi Yabe Kouichi Odagaki Department of Mechanical Sciences and Engineering Tokyo Institute of Technology2-12-1 Meguro-kuOokayama 152-8552Japan

A new multi-dimensional scheme for the Maxwell equations is established by the CIP method in combination with the method of characteristics(CIP-MOC).In addition,the CIP-MOC can be extended to arbitrary grid system by the Soroban grid without losing the third-order *** the accuracy fixed,the grid points required for the CIP are 40 times less than the conventional schemes like the FDTD in three *** solutions obtained by the CIP-MOC are compared with analytical solution and the FDTD in plane-wave scattering by a perfectly-conducting circular cylinder,and the CIP-MOC agrees very well with analytical *** Soroban grid is also applied to the vlasov equation that describes the kinematics of plasmas that is frequently combined with the Maxwell *** adaptively moving points in velocity space are similar to the particle codes but can provide accurate solutions.

关键词： Maxwell equation vlasov equation CIP method method of characteristics Soroban grid

GLOBAL WEAK SOLUTIONS OF THE RELATIVISTIC vlasov-KLEIN-GORDON SYSTEM IN TWO DIMENSIONS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Annals of Differential equations 2007年第4期23卷 511-518页

作者： Wei Mingjun Zhu Wanzhen School of Science Zhejiang University of Science and Technology Hangzhou 310023

In this paper we consider the system of classical particles coupled with a Klein-Gordon field in two dimensions. We establish a-priori-bounds on the solutions of this system with initial data satisfying a size restriction derived from conservation of energy. This result, together with the smoothing of ＂velocity averaging＂, yields the existence of global weak solutions to the corresponding restricted initial value problem. The size restriction is necessary since energy of the system is indefinite. Finally, we show that the weak solutions preserve the total mass.

关键词： global weak solutions vlasov equation Klein-Gordon equation