Efficient large-scale forcing in finite-difference simulations of steady isotropic turbulence

This study proposes a new forcing scheme suitable for massively-parallel finite-difference simulations of steady isotropic turbulence. The proposed forcing scheme, named reduced-communication forcing (RCF), is based on the idea of the conventional large-scale forcing, but requires much less data communication, leading to a high parallel efficiency. It has been confirmed that the RCF works intrinsically in the same manner as the conventional large-scale forcing. Comparisons have revealed that the fourth-order finite-difference model run in combination with the RCF (FDM-RCF) is as good as the spectral model, while requiring less computational costs.