Strategies for Accelerating Nonlinear Convergence for ${\rm T}{\hbox {-}}\Omega$ Formulation

This paper details the derivation of the Jacobian matrix and the residual vector associated with the Newton-Raphson iteration sequence in terms of the T-Ω formulation. Then, a scheme is proposed to efficiently find the optimum relaxation factor for improving global convergence. Furthermore, to address some local convergence issues, a local damping factor that damps the updating of the nonlinear material property for the evaluation of Jacobian matrix during nonlinear iteration is introduced.