Quasi-radial basis functions applied to boundary element solutions for the Grad-Shafranov equation

概要

論文の詳細を見る
The Grad-Shafranov equation for axisymmetric fusion plasma has been transformed into a boundary integral equation by expanding the inhomogeneous current density term into a set of 'quasi' radial basis functions (RBFs). These quasi RBFs are derived in such a way that a particular solution for the Grad-Shafranov equation will be a simple Gaussian function. Two or three stages of eigenvalue iterations are required together with a nonlinear optimization to update the scaling factor of each quasi RBF It has been found that excellent accuracy of the boundary element solution can be realized with a small number of quasi RBFs when adopting RBF-dependent scaling factors.