Lattice Boltzmann simulations for multiple tidal turbines using actuator line model

In numerical simulations of tidal current farms, large-scale computational fluid dynamic (CFD) simulations with a high-resolution grid are required to calculate the interactions between tidal turbines. In this study, we develop a numerical simulation method for tidal current turbines using the lattice Boltzmann method (LBM), which is suitable for large-scale CFD simulations. Tidal turbines are modeled by using the actuator line (ACL) model, which represents each blade as a group of actuator points in a line. In order to validate our LBM-ACL model, we perform simulations for two interacting tidal turbines, and results of turbine performance are compared with a water tank experiment. The proposed model successfully reproduces the variation of the torque due to wave effects and mean turbine performance. We have demonstrated a large-scale simulation for ten tidal turbines using 8.55×10⁸ grid points and 16 GPUs of Tesla P100 and the simulation has been completed within 9 hours with the LBM performance of 392 MLUPS per GPU.