2018 journal article
UPSCALING AND DOWNSCALING APPROACHES IN LES-ODT FOR TURBULENT COMBUSTION FLOWS
INTERNATIONAL JOURNAL FOR MULTISCALE COMPUTATIONAL ENGINEERING, 16(1), 45β76.
The multiscale LES-ODT approach in turbulent combustion is based on a hybrid temporal and spatial coupling of a coarse 3D large-eddy simulation (LES) with embedded fine-grained 1D solutions for momentum and thermochemical scalars using the one-dimensional turbulence (ODT) model. Schemes for coupling LES and ODT using wavelet-based approaches for downscaling (information passing from LES to ODT) and the Kalman filter for upscaling (passing statistics from ODT to LES) are developed. Comparison between direct numerical simulation (DNS) and LES-ODT predictions are performed for various turbulence and turbulent combustion cases, including autoignition in non-homogeneous mixtures and twin premixed flames. The results show that the developed upscaling and downscaling schemes predict reasonably well statistics of the combustion problems investigated.