Numerical comparison of variational methods for solving the linear algebraic equation system obtained after finite-difference approximation of the convection-diffusion equation

It is after necessary one often has to solve very large linear unsymmetric systems in realistic scientific modelling. An efficient class of iterative methods for solving these systems is composed of the variational methods. BiCG and GMRES(IO) methods from this class were considered. Numerical investigation was carried out by the model of the linear algebraic equation system generated by finite-difference approximation of the convection-diffusion equation. Numerical results allowed to define domain of applicability of methods are obtained.