Numerical Simulations of Reacting and Nonreacting Flows Using Asynchrony-tolerant Schemes for Exascale Computing
Emmet Cleary, California Institute of Technology
Communication and data synchronization between processing elements (PEs) are likely to pose a major challenge in the scalability of solvers at the exascale. Recently developed asynchrony-tolerant (AT) finite difference schemes address this issue by relaxing communication and synchronization between PEs at a mathematical level while preserving accuracy, resulting in improved scalability. The performance of these schemes has been validated for simple linear and nonlinear homogeneous PDEs. However, many problems of practical interest are governed by highly nonlinear PDEs with source terms, whose solution may be sensitive to perturbations caused by communication asynchrony. The current work applies the AT schemes to the one-dimensional Navier-Stokes equation for traveling waves, oscillating waves with noise to mimic turbulence, and reacting flow with a single-step hydrogen mechanism. Error analysis will be discussed both in physical and spectral space. Results show that additional errors introduced by the AT schemes, even with the highly nonlinear and temperature sensitive chemical source terms in the reacting flow case, are negligible and the schemes preserve their accuracy.
Abstract Author(s): Emmet M. Cleary, Konduri Aditya, Jacqueline H. Chen