A high order semi-Lagrangian discontinuous Galerkin method for the two-dimensional incompressible Euler equations and the guiding center Vlasov model without operator splitting
This work extends a high-order numerical method to important fluid and plasma models, but it is an incremental extension of existing techniques.
The authors generalized a high-order semi-Lagrangian discontinuous Galerkin method to solve 2D incompressible Euler equations and the guiding center Vlasov model without operator splitting, using an adaptive time-stepping strategy to avoid cell distortion. Numerical results demonstrate the method's effectiveness.
In this paper, we generalize a high order semi-Lagrangian (SL) discontinuous Galerkin (DG) method for multi-dimensional linear transport equations without operator splitting developed in Cai et al. (J. Sci. Comput. 73: 514-542, 2017) to the 2D time dependent incompressible Euler equations in the vorticity-stream function formulation and the guiding center Vlasov model. We adopt a local DG method for Poisson's equation of these models. For tracing the characteristics, we adopt a high order characteristics tracing mechanism based on a prediction-correction technique. The SLDG with large time-stepping size might be subject to extreme distortion of upstream cells. To avoid this problem, we propose a novel adaptive time-stepping strategy by controlling the relative deviation of areas of upstream cells.