We design and analyze up to third order accurate discontinuous Galerkin (DG) methods satisfying a strict maximum principle for Fokker–Planck equations. A procedure is established to identify an effective test set in each computational cell to ensure the desired bounds of numerical averages during time evolution. This is achievable by taking advantage of the two parameters in the numerical flux ...

To investigate blob properties in the tokamak scrape-off layer (SOL), we perform dedicated numerical nonlinear simulations of plasma turbulence in the SOL of a TCV discharge using the Global Braginskii Solver code. A blob detection technique is used for the first time in a threedimensional (3D) full-turbulence simulation to track the motion of the filaments in the SOL. The specific size, densit...

Computational Fluid Dynamics (CFD) is used as a common design tool in the aerospace industry. UPACS, a package for CFD, is convenient for users, since a customized simulator can be built just by selecting desired functions. The problem is its computation speed, which is difficult to enhance by using the clusters due to its complex memory access patterns. As an economical solution, accelerators ...

In this work, we propose a residual-based posteriori error estimator for algebraic flux-corrected (AFC) schemes stationary convection-diffusion equations. A global upper bound is derived the in energy norm general choice of limiter, which defines nonlinear stabilization term. diffusion-dominated regime, has same convergence properties as true error. second approach discussed, where way using St...

Micro pulse lidar is a promising tool for retrieving the convective boundary layer height (CBLH), but its application has been hindered by sharp extinction of the signal in high humidity conditions, e.g., clouds. To remedy this, we developed an effective and simple limiter to obtain more accurate estimates of the CBLH. The limiter is based on the algorithm for the convective condensation level ...

In this paper we generalize a new type of compact Hermite weighted essentially nonoscillatory (HWENO) limiter for the Runge-Kutta discontinuous Galerkin (RKDG) methods, which were recently developed in [34] for structured meshes, to two dimensional unstructured triangular meshes. The main idea of this limiter is to reconstruct the new polynomial using the entire polynomials of the DG solution f...

An experiment is described in which plasma flow to a tokamak limiter is controlled through the use of a local toroidal divertor coil mounted inside the limiter itself. This coil produces a local perturbed field Be approximately equal to the local unperturbed toroidal field B r ~ 3 kG, such that when Be adds to Br the field lines move into the limiter and the local plasma flow to it increases by...

Thermal electron transport plays an important role in the performance of direct-drive inertial-confinement-fusion targets. The laser energy absorbed in the corona is carried into the dense target through thermal electron transport and is converted into kinetic energy through the ablation process. The efficiency of the target drive and of the absorption of the laser light depend to a large exten...

In this work we propose a second order flux limiter finite volume method, named PVM-2U-FL, that only uses information of the two external waves of the hyperbolic system. This method could be seen as a natural extension of the well known WAF method introduced by Prof. Toro in [21]. We prove that independently of the number of unknowns of the 1D system, it recovers the second order accuracy at re...

A new approach to the derivation of local extremum diminishing finite element schemes is presented. The monotonicity of the Galerkin discretization is enforced by adding discrete diffusion so as to eliminate all negative off-diagonal matrix entries. The resulting low-order operator of upwind type acts as a preconditioner within an outer defect correction loop. A generalization of TVD concepts i...