A new fully two-dimensional conservative semi-Lagrangian method: applications on polar grids, from diocotron instability to ITG turbulence
نویسندگان
چکیده
While developing a new semi-Lagrangian solver, the gap between a linear Landau run in 1D×1D and a 5D gyrokinetic simulation in toroidal geometry is quite huge. Intermediate test cases are welcome for testing the code. A new fully two-dimensional conservative semi-Lagrangian (CSL) method is presented here and is validated on 2D polar geometries. We consider here as building block, a 2D guiding-center type equation on an annulus and apply it on two test cases. First, we revisit a 2D test case previously done with a PIC approach [18] and detail the boundary conditions. Second, we consider a 4D drift-kinetic slab simulation (see [10]). In both cases, the new method appears to be a good alternative to deal with this type of models since it improves the lack of mass conservation of the standard semi-Lagrangian (BSL) method. PACS. PACS-key 52.30.GzGyrokinetics – PACS-key 52.65.FfPlasma simulation: Fokker-Planck and Vlasov equation
منابع مشابه
Semi-Lagrangian simulations on polar grids: from diocotron instability to ITG turbulence
While developing a new semi-Lagrangian solver, the gap between a linear Landau run in 1D×1D and a 5D gyrokinetic simulation in toroidal geometry is quite huge. Intermediate test cases are welcome for checking the code. We consider here as building block, a 2D guiding-center type equation on an annulus. We first revisit a 2D test case previously done with a PIC approach [16] and detail the bound...
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