Numerical Algorithms for Axisymmetric Fokker-planck-landau Operators
نویسنده
چکیده
We establish a simpliied form of the axisymmetric Fokker-Planck-Landau operator. In doing so, we derive a weak formulation of this operator on which we get directly the conservation properties and the decay of the entropy as it is the case for the three dimensional operator 6]. A symmetrized version of this formulation leads to a class of numerical schemes which satisfy these physical properties at the discrete level. Fast numerical algorithms used in 5] 15] are shown to be eecient in the cylindrical geometry. Finally, some numerical tests are presented at the end of this paper.
منابع مشابه
Fast Algorithms for Numerical, Conservative and Entropy Approximations of the Fokker-planck-landau Equation
abstract We present fast numerical algorithms to solve the non linear Fokker-Planck-Landau equation in 3-D velocity space. The discretization of the collision operator preserves the properties required by the physical nature of the Fokker-Planck-Landau equation, such as the conservation of mass, momentum and energy, the decay of the entropy, and the fact that the steady states are Maxwellians. ...
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