A multiple-resolution strategy for Direct Numerical Simulation of scalar turbulence


In this paper a numerical procedure to simulate low diffusivity scalar turbulence is presented. The method consists of using a grid for the advected scalar with a higher spatial resolution than that of the momentum. The latter usually requires a less refined mesh and integrating both fields on a single grid tailored to the most demanding variable produces an unnecessary computational overhead. A multiple resolution approach is used also in the time integration in order to maintain the stability of the scalars on the finer grid. The method is the more advantageous the less diffusive the scalar is with respect to momentum, therefore it is particularly well suited for large Prandtl or Schmidt number flows. However, even in the case of equal diffusivities the present procedure gives CPU time and memory occupation savings, due to the increased gradients and more intermittent behaviour of the scalars when compared to momentum.



Multiple resolution, Direct numerical simulation, Scalar turbulance


Copyright 2015 Journal of Computational Physics.This is a pre-print version of a published paper that is available at: https://www.sciencedirect.com/science/article/pii/S0021999115005586?via%3Dihub. Recommended citation: Ostilla-Monico, Rodolfo, Yantao Yang, Erwin P. van der Poel, Detlef Lohse, and Roberto Verzicco. "A multiple-resolution strategy for Direct Numerical Simulation of scalar turbulence." Journal of computational physics 301 (2015): 308-321. doi:10.1017/jfm.2015.675. This item has been deposited in accordance with publisher copyright and licensing terms and with the author's permission.