TY - JOUR U1 - Zeitschriftenartikel, wissenschaftlich - nicht begutachtet (unreviewed) A1 - Bedrunka, Mario Christopher A1 - Wilde, Dominik A1 - Kliemank, Martin A1 - Reith, Dirk A1 - Foysi, Holger A1 - Krämer, Andreas T1 - Lettuce: PyTorch-based Lattice Boltzmann Framework N2 - The lattice Boltzmann method (LBM) is an efficient simulation technique for computational fluid mechanics and beyond. It is based on a simple stream-and-collide algorithm on Cartesian grids, which is easily compatible with modern machine learning architectures. While it is becoming increasingly clear that deep learning can provide a decisive stimulus for classical simulation techniques, recent studies have not addressed possible connections between machine learning and LBM. Here, we introduce Lettuce, a PyTorch-based LBM code with a threefold aim. Lettuce enables GPU accelerated calculations with minimal source code, facilitates rapid prototyping of LBM models, and enables integrating LBM simulations with PyTorch's deep learning and automatic differentiation facility. As a proof of concept for combining machine learning with the LBM, a neural collision model is developed, trained on a doubly periodic shear layer and then transferred to a different flow, a decaying turbulence. We also exemplify the added benefit of PyTorch's automatic differentiation framework in flow control and optimization. To this end, the spectrum of a forced isotropic turbulence is maintained without further constraining the velocity field. KW - Pytorch KW - Automatic Differentiation KW - Neural networks KW - Machine learning KW - Lattice Boltzmann Method Code U6 - https://doi.org/10.48550/arXiv.2106.12929 DO - https://doi.org/10.48550/arXiv.2106.12929 AX - 2106.12929 PB - arXiv ER -