A hybrid method of semi-Lagrangian and additive semi-implicit Runge-Kutta schemes for gyrokinetic Vlasov simulations

作者：Maeyama S^*; Ishizawa A; Watanabe T H; Nakajima N; Tsuji Iio S; Tsutsui H

来源：Computer Physics Communications, 2012, 183(9): 1986-1992.

DOI：10.1016/j.cpc.2012.04.028

• Gyrokinetics
• Vlasov simulation
• Operator splitting method
• Semi-Lagrangian scheme
• Additive semi-implicit Runge-Kutta scheme

A hybrid method of semi-Lagrangian and additive semi-implicit Runge-Kutta schemes is developed for gyrokinetic Vlasov simulations in a flux tube geometry. The time-integration scheme is free from the Courant-Friedrichs-Lewy condition for the linear advection terms in the gyrokinetic equation. The new method is applied to simulations of the ion-temperature-gradient instability in fusion plasmas confined by helical magnetic fields, where the parallel advection term severely restricts the time step size for explicit Eulerian schemes. Linear and nonlinear results show good agreements with those obtained by using the explicit Runge-Kutta-Gill scheme, while the new method substantially reduces the computational cost.

• 出版日期2012-9