A Hybrid MPI-OpenMP Parallel Implementation for pseudospectral simulations with application to Taylor-Couette Flow

Abstract

A hybrid-parallel direct-numerical-simulation method with application to turbulent Taylor-Couette flow is presented. The Navier-Stokes equations are discretized in cylindrical coordinates with the spectral Fourier-Galerkin method in the axial and azimuthal directions, and high-order finite differences in the radial direction. Time is advanced by a second-order, semi-implicit projection scheme, which requires the solution of five Helmholtz/Poisson equations, avoids staggered grids and renders very small slip velocities. Nonlinear terms are computed with the pseudospectral method. The code is parallelized using a hybrid MPI-OpenMP strategy, which is simpler to implement, reduces inter-node communications and is more efficient compared to a flat MPI parallelization. A strong scaling study shows that the hybrid code maintains very good scalability up to more than 20000 processor cores and thus allows to perform simulations at higher resolutions than previously feasible, and opens up the possibility to simulate turbulent Taylor-Couette flows at Reynolds numbers up to $\mathcal{O}(10^5)$. This enables to probe hydrodynamic turbulence in Keplerian flows in experimentally relevant regimes.

30 pages, 11 figures

References in corpus (6)

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• Computational Study of Turbulent-Laminar Patterns in Couette Flow
• Stability and angular-momentum transport of fluid flows between corotating cylinders
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Cited by in corpus (13)

• Dynamics of viscoelastic pipe flow in the maximum drag reduction limit
• Effects of the computational domain size on direct numerical simulations of Taylor-Couette turbulence with stationary outer cylinder
• Conductive and convective heat transfer in fluid flows between differentially heated and rotating cylinders
• Boundary-layer turbulence in experiments of quasi-Keplerian flows
• Transition to magnetorotational turbulence in Taylor--Couette flow with imposed azimuthal magnetic field
• Hydrodynamic turbulence in quasi-Keplerian rotating flows
• Phase-field simulation of core-annular pipe flow
• Vortex merging and splitting events in viscoelastic Taylor Couette flow
• nsCouette -- A high-performance code for direct numerical simulations of turbulent Taylor-Couette flow
• Reynolds number scaling of influence of boundary layers on the global behavior of laboratory quasi-Keplerian flows
• Nonlinear waves in stratified Taylor--Couette flow. Part 1. Layer formation
• Nonlinear waves in stratified Taylor--Couette flow. Part 2. Buoyancy flux
• Phase Slip Solutions in Magnetically Modulated Taylor-Couette Flow