Strategies for Accelerating Nonlinear Convergence for T-Ω Formulation

This paper details the derivation of the Jacobian matrix and the residual vector associated with the Newton–Raphson iteration sequence in terms of theT-Ωformulation. 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.