For external flows the AS performs better when it is applied in all grid levels of the multigrid method, while for internal flows the best performance is achieved when AS is applied in the finest grid only.
While multigrid methods can be applied in irregular domains (and to a broader class of partial differential equations), they are difficult to implement in a robust fashion, since they require an appropriate hierarchy of coarse grids, which are not provided in many practical situations.
In particular, algebraic multigrid preconditioners (AMG) have been applied to the bidomain equations, often outperforming standard methods like the ILU or the block Jacobi preconditioner adopted in this work [ 31].
A nonlinear multigrid strategy has also been applied to the outer pseudo-time loop to try to provide a better handling of the nonlinearities of the equations and increase the convergence rate.
As a result, the proposed hybrid domain decomposition/multigrid method can be viewed as a particular form of parallel multigrid in which multigrid acceleration is applied on a subdomain basis, these local calculations being coordinated by an appropriate domain decomposition iteration at the global level.
Finite-element multigrid method is applied to two-dimensional elastic wave equation in frequency domain.
Finally, this analysis is applied to design a very efficient multigrid solver for semi-structured triangular grids, based on a hybrid-smoother.
In the second example, SBR algorithm coupled to multigrid approach is applied to estimate the 1-D modes from a simulated 1-D modal signal expressed in (5) with 30 samples embedded in additive Gaussian white noise such that the SNR is 23 dB.
An algebraic multigrid solver is applied to solve the discrete system.
Thus, a multigrid strategy can be applied.
