A multi-rigid body approach for actuator line model with controls in a lattice Boltzmann framework for wind turbine modeling

This paper presents an improved actuator line model (ALM) for wind turbine modeling. A multi-rigid body system and multiple control systems are incorporated to overcome limitations observed in conventional ALM, which are one-way coupling and the need for artificial parameters such as rotational speed, blade pitch angle, and yaw direction, which could introduce inaccuracies when applied to large-scale simulations. Furthermore, an entropic lattice Boltzmann method (ELBM) solver is used for flow field simulation. This model's efficacy is verified with conditions that match those of another study, using the widely studied NREL (National Renewable Energy Laboratory) 5 MW wind turbine. Additional comparison is also made with particle imaging velocimetry (PIV) measurements using a scaled NREL UAE Phase IV turbine. The utility of this model is demonstrated in the context of a single turbine under various wind speeds and two turbines in tandem with different spacings and wind speeds, showcasing its efficiency and accuracy.