000255224 001__ 255224
000255224 005__ 20190619220028.0
000255224 0247_ $$a10.1016/j.jcp.2019.03.050$$2doi
000255224 037__ $$aARTICLE
000255224 245__ $$aDiscontinuous Galerkin Discretizations of the Boltzmann Equations in 2D: semi-analytic time stepping and absorbing boundary layers
000255224 260__ $$c2018
000255224 269__ $$a2018
000255224 336__ $$aJournal Articles
000255224 520__ $$aWe present an efficient nodal discontinuous Galerkin method for approximating nearly incompressible flows using the Boltzmann equations. The equations are discretized with Hermite polynomials in velocity space yielding a first order conservation law. A stabi- lized unsplit perfectly matching layer (PML) formulation is introduced for the resulting nonlinear flow equations. The proposed PML equations exponentially absorb the dif- ference between the nonlinear fluctuation and the prescribed mean flow. We introduce semi-analytic time discretization methods to improve the time step restrictions in small relaxation times. We also introduce a multirate semi-analytic Adams-Bashforth method which preserves efficiency in stiff regimes. Accuracy and performance of the method are tested using distinct cases including isothermal vortex, flow around square cylinder, and wall mounted square cylinder test cases.
000255224 6531_ $$aPerfectly matching layer
000255224 6531_ $$aSemi-analytic
000255224 6531_ $$aMultirate
000255224 6531_ $$aBoltzmann equation
000255224 6531_ $$aDiscontinuous Galerkin
000255224 6531_ $$aGPU
000255224 700__ $$aKarakus, A
000255224 700__ $$aChalmers, N.
000255224 700__ $$g232231$$aHesthaven, Jan S.$$0247428
000255224 700__ $$aWarburton, T
000255224 8560_ $$fjan.hesthaven@epfl.ch
000255224 8564_ $$uhttps://infoscience.epfl.ch/record/255224/files/DGBoltzmannPML.pdf$$s7422563
000255224 8564_ $$uhttps://infoscience.epfl.ch/record/255224/files/DGBoltzmannPML.pdf?subformat=pdfa$$s9769525$$xpdfa
000255224 909C0 $$pMCSS$$mdelphine.vieira@epfl.ch$$mjan.hesthaven@epfl.ch$$0252492$$xU12703
000255224 909CO $$qGLOBAL_SET$$pSB$$particle$$ooai:infoscience.epfl.ch:255224
000255224 960__ $$ajan.hesthaven@epfl.ch
000255224 961__ $$aalain.borel@epfl.ch
000255224 973__ $$rREVIEWED$$sPUBLISHED$$aOTHER
000255224 980__ $$aARTICLE
000255224 981__ $$aoverwrite