2D pseudo-spectral parallel Navier-Stokes simulations of compressible Rayleigh-Taylor instability

A 2D Fourier-Chebyshev pseudo-spectral numerical method for the full Navier-Stokes equations with a dynamical domain decomposition technique has been parallelized on a SPMD machine, a CRAY-T3E. The parallelism is based on the distribution of data among processors and on simultaneous computations on each subdomain. The SHMEM paradigm is used for communication between processors. Comparisons between the vectorial and the parallel versions of spectral derivatives with Fourier and Chebyshev expansions are presented. Performances versus the number of processors and collocation points are also studied. The numerical code is then used to simulate single and multimode Rayleigh Taylor flows. The influence of the physical diffusion between species is emphasized on a single mode configuration. A simulation with 22 initial perturbation modes is also carried out and analyzed. (C) 2002 Elsevier Science Ltd. All rights reserved.