A pencil distributed finite difference code for strongly turbulent wall-bounded flows. (15th August 2015)

• Record Type: Journal Article
• Authors: van der Poel, Erwin P.; Ostilla-Mónico, Rodolfo; Donners, John; Verzicco, Roberto
• Is Part Of: Computers & fluids. Volume 116(2015)
• Page Start: 10
• Page End: 16
• Publication Date: 2015-08-15
• Subjects: Finite-difference scheme -- Turbulent flows -- Rayleigh–Bénard convection -- Taylor–Couette flow -- Parallelization; Fluid dynamics -- Data processing -- Periodicals; 532.050285
• DOI: 10.1016/j.compfluid.2015.04.007
• Languages: English
• ISSNs: 0045-7930

Abstract

Abstract: We present a numerical scheme geared for high performance computation of wall-bounded turbulent flows. The number of all-to-all communications is decreased to only six instances by using a two-dimensional (pencil) domain decomposition and utilizing the favourable scaling of the CFL time-step constraint as compared to the diffusive time-step constraint. As the CFL condition is more restrictive at high driving, implicit time integration of the viscous terms in the wall-parallel directions is no longer required. This avoids the communication of non-local information to a process for the computation of implicit derivatives in these directions. We explain in detail the numerical scheme used for the integration of the equations, and the underlying parallelization. The code is shown to have very good strong and weak scaling to at least 64 K cores.