We present an Anderson acceleration-based approach to spatially couple three-dimensional Lattice Boltzmann and Navier–Stokes (LBNS) flow simulations. This allows to locally exploit the computational features of both fluid flow solver approaches to the fullest extent and yields enhanced control to match the LB and NS degrees of freedom within the LBNS overlap layer. Designed for parallel Schwarz coupling, the Anderson acceleration allows for the simultaneous execution of both Lattice Boltzmann and Navier–Stokes solver. We detail our coupling methodology, validate it, and study convergence and accuracy of the Anderson accelerated coupling, considering three steady-state scenarios: plane channel flow, flow around a sphere and channel flow across a porous structure. We find that the Anderson accelerated coupling yields a speed-up (in terms of iteration steps) of up to 40% in the considered scenarios, compared to strictly sequential Schwarz coupling.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledged KAUST grant number(s): UK-C0020
Acknowledgements: This work was partially supported by the Award No. UK-C0020 made by King Abdullah University of Science and Technology (KAUST), and by the priority program “1648 Software for Exascale Computing” of the German Research Foundation (DFG). The financial support of the Institute for Advanced Study (IAS) of the Technical University of Munich is acknlowedged. We further thank the Munich Centre of Advanced Computing (MAC) for providing computational resources.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.