Novel multigrid orientated solution adaptive time‐step approaches

New performance-improving natural compatabilities between multigrid convergence acceleration and adapted time-step solution procedures are discussed. Echoing the multigrid-coarsened space-steps and interpolations, a novel adaptive temporal ‘subcycling’ strategy is presented. Tests show, saving storage by basing time-steps on a focused relatively high unsteadiness region, a focused range of variables or multigrid restricted/injected variables can be effective. A novel strategy of advancing comparative solution elements on coarser multigrid levels is found to give time savings. Higher frequency spatial components are accounted for on coarse levels through the multigrid forcing function. Copyright 2002 John Wiley & Sons, Ltd.

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