Influence of limiting the projection region on coarse Large Eddy Simulation-Actuator Line Model simulations

Abstract

Wind energy has developed worldwide, becoming a mature technology. Nevertheless, major advances regarding wind turbine aerodynamics and control as well as wind farm control and its integration in the power grid are being foreseen in the near future. To accomplish that, different simulation tools have emerged. The Actuator Line Model (ALM) in the frame of Large Eddy Simulation method has been used to study different related topics, from wake stability to wind turbine interaction and wind farm control, and it is considered the state of the art to simulate with high fidelity the wind flow through wind turbines and wind farms. Despite that, the ALM results, particularly loads and power production, have shown to be dependent on the numerical setup, like the projection function and its smearing parameter. The present paper aims to contribute to the latter by showing the influence of limiting the projection region. It is found that projecting the aerodynamic forces onto a cylinder that confines the rotor disk improves the computed power and loads compared to a Blade Element Momentum code and affects the wake development.

Estimation of wind turbine wakes with generative-adversarial networks

“…The wind turbine rotors are represented as body forces with the ALM, smearing the aerodynamic forces onto the computational domain with the strategy proposed in Ref. [14]. The layouts could represent different wind turbine positions given a fixed wind direction (West) or the same wind turbine positions for different wind directions (similar procedure as the one used in Ref.…”

Large eddy simulation of an onshore wind farm under different operating regimes including topographic effects

“…LES-ALM simulations are performed with the open source finite volume code caffa3d [23,24], that has been validated for wind energy applications, for both wind tunnel and actual wind farm cases, [4,5,25], including the recently proposed limitation to the projection region of the aerodynamic forces [26]. A brief description of the numerical domain and numerical setup is given below.…”

Assessment of a heterogeneous computing CFD code in wind farm simulations

“…To project these forces in the computational domain, a Gaussian smearing function is used to smoothly distribute the forces and thus avoid the occurrence of numerical instabilities [11]. This smearing function is limited to a cylindrical volume confined within the rotor disc, as it has been shown to improve force distribution near the blade tip [16]. The distributed forces are finally used to compute additional source term in the Navier-Stokes equations.…”