We have defined and analyzed a semi-Toeplitz preconditioner for time-dependent and steady-state convection-diffusion problems. Analytic expressions for the eigenvalues of the preconditioned systems are obtained. An asymptotic analysis shows that the eigenvalue spectrum of the time-dependent problem is reduced to two eigenvalues when the number of grid… (More)
A semi-Toeplitz preconditioner for the linearized Navier– Stokes equation for compressible flow is proposed and tested. The pre-conditioner is applied to the linear system of equations to be solved in each time step of an implicit method. The equations are solved with flat plate boundary conditions and are linearized around the Blasius solution. The grids… (More)
We have defined and analyzed a semi-Toeplitz preconditioner for time-dependent and steady-state convection-diffusion problems. The preconditioner exhibits very good theoretical convergence properties. The analysis is corroborated by numerical experiments.