Implicit Multigrid Computation of Unsteady Flows with Applications to Aeroelasticity

Abstract

An implicit, multigrid scheme is extended to treat unsteady flows using the concept of temporal subiteration (or dual-time stepping, as it sometimes is called). The scheme is applied to compute the unsteady flow past fixed and moving circular cylinders at moderate Reynolds numbers. The observed pattern of periodic vortex shedding is computed for fixed cylinders, and the dimensionless frequency of this phenomenon (the Strouhal number) is compared with experimentally determined values. The efficiency of the subiterated, multigrid approach is discussed. Finally, solutions for the coupled problem in which the motion of the cylinder is determined by the aerodynamic forcing are computed and compared with the results of other researchers.KeywordsReynolds NumberMach NumberCoarse GridUnsteady FlowStrouhal NumberThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.