Augmented conjugate gradient. Application in an iterative process for the solution of scattering problems
The paper presents the application of the augmented conjugate gradient method in an iterative process applied to the solution of acoustic scattering problems. The basic idea of this conjugate gradient method is to use a Krylov subspace generated by the first linear system to define an initial guess and modified descent directions to solve the following systems with the same matrix and the right-hand sides depend on the previous solutions. An exact controllability approach is used, a least-squares formulation is introduced and solved by a preconditioned conjugate gradient algorithm. Numerical results with emphasis on the efficiency of the augmented conjugate gradient to solve linear systems associated to the preconditioner are given.
scientific article; zbMATH DE number 1234726