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Song Jiang - One of the best experts on this subject based on the ideXlab platform.

  • low mach number limit of full navier stokes equations in a 3d Bounded Domain
    2015
    Co-Authors: Changsheng Dou, Song Jiang
    Abstract:

    Abstract This paper studies the low Mach number limit of the full compressible Navier–Stokes equations in a three-dimensional Bounded Domain where the velocity field and the temperature satisfy the slip boundary conditions and the Neumann boundary condition, respectively. The uniform estimates in the Mach number for the strong solutions are derived in a short time interval, provided that the initial density and temperature are close to the constant states and satisfy the “Bounded derivative conditions”. Thus the solutions of the full compressible Navier–Stokes equations converge to the one of the isentropic incompressible Navier–Stokes equations, as the Mach number vanishes.

  • on instability and stability of three dimensional gravity driven viscous flows in a Bounded Domain
    2014
    Co-Authors: Fei Jiang, Song Jiang
    Abstract:

    Abstract We investigate the instability and stability of some steady-states of a three-dimensional nonhomogeneous incompressible viscous flow driven by gravity in a Bounded Domain Ω of class C 2 . When the steady density is heavier with increasing height (i.e., the Rayleigh–Taylor steady-state), we show that the steady-state is linear unstable (i.e., the linear solution grows in time in H 2 ) by constructing a (standard) energy functional and exploiting the modified variational method. Then, by introducing a new energy functional and using a careful bootstrap argument, we further show that the steady-state is nonlinear unstable in the sense of Hadamard. When the steady density is lighter with increasing height, we show, with the help of a restricted condition imposed on steady density, that the steady-state is linearly globally stable and nonlinearly asymptotically stable in the sense of Hadamard.

  • on instability and stability of three dimensional gravity driven viscous flows in a Bounded Domain
    2013
    Co-Authors: Fei Jiang, Song Jiang
    Abstract:

    We investigate the instability and stability of some steady-states of a three-dimensional nonhomogeneous incompressible viscous flow driven by gravity in a Bounded Domain $\Omega$ of class $C^2$. When the steady density is heavier with increasing height (i.e., the Rayleigh-Taylor steady-state), we show that the steady-state is linear unstable (i.e., the linear solution grows in time in $H^2$) by constructing a (standard) energy functional and exploiting the modified variational method. Then, by introducing a new energy functional and using a careful bootstrap argument, we further show that the steady-state is nonlinear unstable in the sense of Hadamard. When the steady density is lighter with increasing height, we show, with the help of a restricted condition imposed on steady density, that the steady-state is linearly globally stable and nonlinearly locally stable in the sense of Hadamard.

  • On multi-dimensional compressible flows of nematic liquid crystals with large initial energy in a Bounded Domain
    2013
    Co-Authors: Fei Jiang, Song Jiang, Dehua Wang
    Abstract:

    Abstract We study the global existence of weak solutions to a multi-dimensional simplified Ericksen–Leslie system for compressible flows of nematic liquid crystals with large initial energy in a Bounded Domain Ω ⊂ R N , where N = 2 or 3 . By exploiting a maximum principle, Nirenbergʼs interpolation inequality and a smallness condition imposed on the N-th component of initial direction field d 0 to overcome the difficulties induced by the supercritical nonlinearity | ∇ d | 2 d in the equations of angular momentum, and then adapting a modified three-dimensional approximation scheme and the weak convergence arguments for the compressible Navier–Stokes equations, we establish the global existence of weak solutions to the initial-boundary problem with large initial energy and without any smallness condition on the initial density and velocity.

Nader Masmoudi - One of the best experts on this subject based on the ideXlab platform.

  • boundary layers and incompressible navier stokes fourier limit of the boltzmann equation in Bounded Domain i
    2017
    Co-Authors: Ning Jiang, Nader Masmoudi
    Abstract:

    We establish the incompressible Navier-Stokes-Fourier limit for solutions to the Boltzmann equation with a general cutoff collision kernel in a Bounded Domain. Appropriately scaled families of DiPerna-Lions(-Mischler) renormalized solutions with Maxwell reflection boundary conditions are shown to have fluctuations that converge as the Knudsen number goes to 0. Every limit point is a weak solution to the Navier-Stokes-Fourier system with different types of boundary conditions depending on the ratio between the accommodation coefficient and the Knudsen number. The main new result of the paper is that this convergence is strong in the case of the Dirichlet boundary condition. Indeed, we prove that the acoustic waves are damped immediately; namely, they are damped in a boundary layer in time. This damping is due to the presence of viscous and kinetic boundary layers in space. As a consequence, we also justify the first correction to the infinitesimal Maxwellian that one obtains from the Chapman-Enskog expansion with Navier-Stokes scaling. This extends the work of Golse and Saint-Raymond [20,21] and Levermore and Masmoudi [28] to the case of a Bounded Domain. The case of a Bounded Domain was considered by Masmoudi and Saint-Raymond [34] for the linear Stokes-Fourier limit and Saint-Raymond [41] for the Navier-Stokes limit for hard potential kernels. Neither [34] nor [41] studied the damping of the acoustic waves. This paper extends the result of [34,41] to the nonlinear case and includes soft potential kernels. More importantly, for the Dirichlet boundary condition, this work strengthens the convergence so as to make the boundary layer visible. This answers an open problem proposed by Ukai [46]. © 2016 Wiley Periodicals, Inc.

  • Boundary layers and incompressible Navier-Stokes-Fourier limit of the Boltzmann Equation in Bounded Domain (I)
    2015
    Co-Authors: Ning Jiang, Nader Masmoudi
    Abstract:

    We establish the incompressible Navier-Stokes-Fourier limit for solutions to the Boltzmann equation with a general cut-off collision kernel in a Bounded Domain. Appropriately scaled families of DiPerna-Lions-(Mischler) renormalized solutions with Maxwell reflection boundary conditions are shown to have fluctuations that converge as the Knudsen number goes to zero. Every limit point is a weak solution to the Navier-Stokes-Fourier system with different types of boundary conditions depending on the ratio between the accommodation coefficient and the Knudsen number. The main new result of the paper is that this convergence is strong in the case of Dirichlet boundary condition. Indeed, we prove that the acoustic waves are damped immediately, namely they are damped in a boundary layer in time. This damping is due to the presence of viscous and kinetic boundary layers in space. As a consequence, we also justify the first correction to the infinitesimal Maxwellian that one obtains from the Chapman-Enskog expansion with Navier-Stokes scaling. This extends the work of Golse and Saint-Raymond \cite{Go-Sai04, Go-Sai05} and Levermore and Masmoudi \cite{LM} to the case of a Bounded Domain. The case of a Bounded Domain was considered by Masmoudi and Saint-Raymond \cite{M-S} for linear Stokes-Fourier limit and Saint-Raymond \cite{SRM} for Navier-Stokes limit for hard potential kernels. Both \cite{M-S} and \cite{SRM} didn't study the damping of the acoustic waves. This paper extends the result of \cite{M-S} and \cite{SRM} to the nonlinear case and includes soft potential kernels. More importantly, for the Dirichlet boundary condition, this work strengthens the convergence so as to make the boundary layer visible. This answers an open problem proposed by Ukai \cite{Ukai}.

  • from the boltzmann equation to the stokes fourier system in a Bounded Domain
    2003
    Co-Authors: Nader Masmoudi, Laure Saintraymond
    Abstract:

    We prove that the renormalized solutions of the Boltzmann equation considered in a Bounded Domain with different types of (kinetic) boundary conditions converge to the Stokes-Fourier system with different types of (fluid) boundary conditions when the main free path goes to zero. This extends the work of F. Golse and D. Levermore [9] to the case of a Bounded Domain. © 2003 Wiley Periodicals, Inc.

Laure Saintraymond - One of the best experts on this subject based on the ideXlab platform.

Fei Jiang - One of the best experts on this subject based on the ideXlab platform.

  • on instability and stability of three dimensional gravity driven viscous flows in a Bounded Domain
    2014
    Co-Authors: Fei Jiang, Song Jiang
    Abstract:

    Abstract We investigate the instability and stability of some steady-states of a three-dimensional nonhomogeneous incompressible viscous flow driven by gravity in a Bounded Domain Ω of class C 2 . When the steady density is heavier with increasing height (i.e., the Rayleigh–Taylor steady-state), we show that the steady-state is linear unstable (i.e., the linear solution grows in time in H 2 ) by constructing a (standard) energy functional and exploiting the modified variational method. Then, by introducing a new energy functional and using a careful bootstrap argument, we further show that the steady-state is nonlinear unstable in the sense of Hadamard. When the steady density is lighter with increasing height, we show, with the help of a restricted condition imposed on steady density, that the steady-state is linearly globally stable and nonlinearly asymptotically stable in the sense of Hadamard.

  • on instability and stability of three dimensional gravity driven viscous flows in a Bounded Domain
    2013
    Co-Authors: Fei Jiang, Song Jiang
    Abstract:

    We investigate the instability and stability of some steady-states of a three-dimensional nonhomogeneous incompressible viscous flow driven by gravity in a Bounded Domain $\Omega$ of class $C^2$. When the steady density is heavier with increasing height (i.e., the Rayleigh-Taylor steady-state), we show that the steady-state is linear unstable (i.e., the linear solution grows in time in $H^2$) by constructing a (standard) energy functional and exploiting the modified variational method. Then, by introducing a new energy functional and using a careful bootstrap argument, we further show that the steady-state is nonlinear unstable in the sense of Hadamard. When the steady density is lighter with increasing height, we show, with the help of a restricted condition imposed on steady density, that the steady-state is linearly globally stable and nonlinearly locally stable in the sense of Hadamard.

  • On multi-dimensional compressible flows of nematic liquid crystals with large initial energy in a Bounded Domain
    2013
    Co-Authors: Fei Jiang, Song Jiang, Dehua Wang
    Abstract:

    Abstract We study the global existence of weak solutions to a multi-dimensional simplified Ericksen–Leslie system for compressible flows of nematic liquid crystals with large initial energy in a Bounded Domain Ω ⊂ R N , where N = 2 or 3 . By exploiting a maximum principle, Nirenbergʼs interpolation inequality and a smallness condition imposed on the N-th component of initial direction field d 0 to overcome the difficulties induced by the supercritical nonlinearity | ∇ d | 2 d in the equations of angular momentum, and then adapting a modified three-dimensional approximation scheme and the weak convergence arguments for the compressible Navier–Stokes equations, we establish the global existence of weak solutions to the initial-boundary problem with large initial energy and without any smallness condition on the initial density and velocity.

Jishan Fan - One of the best experts on this subject based on the ideXlab platform.