Lattice Boltzmann high-performance simulations of decaying isotropic turbulence

Abstract

This study investigates high-performance computing (HPC) strategies for improving and reducing the time consumption of the simulations of turbulent flows in periodic boxes at different resolutions using the lattice Boltzmann method (LBM). Isotropic turbulence is a fundamental problem in fluid dynamics that can be considered a good candidate for examining HPC applications. The LBM is a computational method that can be computationally parallelized, hence proper parallelization and vectorization are provided for reducing data volume and data transfer. Simulations of decaying isotropic turbulence at resolutions starting from 323 to 5123 using the LBM are carried out for these purposes. Clear progress for time reduction is achieved in all cases, while different features of the flow fields are depicted, and their characteristics are discussed. Very thin tubes are visualized, and the energy spectra are studied. More than 88%-time reduction is obtained in favor of the HPC using the same hardware resources with the lattice Boltzmann relaxation time 𝝉 = 0.503. All fields are initialized by a forced turbulent field that was simulated in a previous study using the LBM.