Effect of Grid Topology on Numerical Simulations of Flow Fields around Wind Turbine Nacelle Anemometer

Abstract

In this paper, the effect of mesh topology on the numerical predictions of the immediate near wake region of a horizontal axis wind turbine is investigated. The present work focuses on the nacelle anemometry measurements. Steady Reynolds Averaged Navier-Stokes (RANS) equations are applied to describe the airflow around the wind turbine nacelle. The k-ε turbulence model is used. To model the turbine rotor, the approach based on the actuator disc concept is considered. The computational domain has been meshed with five different configurations of grid; namely, quasi-structured, unstructured and three different hybrid grids constituted of blending of quasi-structured and unstructured grids. The obtained results are compared to the available experimental data. The hybrid mesh with quasi-structured grid in the boundary layer region and unstructured grid in the vicinity of the nacelle is found to be more promising to simulate the near wake generated downstream of the wind turbine nacelle and to predict accurately the nacelle anemometry measurements.

Improved Stall Delay Model for HAWT Performance Predictions using 3D Navier-Stokes Solver and Actuator Disk Method

“…Based on the last approach, later, Smaı li and Masson (2003), Smaı li and Masson (2004), Masson and Smaı li (2006) works on the nacelle anemometry of typical HAWT rotors have been reported. Mainly, they tackled the impact of rotor aerodynamic key parameters upon the flow features within the nacelle region, especially, around the anemometer location of 600 kW commercially available HAWT at a distance of 5.7 m. Tata et al (2018) also performed a simulation study on nacelle anemometer using ADM approach, with the emphasis on the effect of grid topology upon numerical predictions accuracy. Wind farm large eddy simulations have been conducted by Stevens et al (2018) where comparison using the Actuator Disk Method (ADM) and the Actuator Line Method (ALM) with wind tunnel experiments have been carried out.…”

A review of Stall Delay Models and their Application on Hybrid Methods

“…Ameur et al [21] used the 2D and 3D ADM computations in order to study the wind rotor/nacelle interaction in a neutral ABL flow, they found that for complex nacelle geometries the 3D ADM computations are required. Tata et al [22] also performed a simulation study on nacelle anemometer using the ADM approach, with the emphasis on the effect of grid topology upon numerical predictions accuracy. Recently, Amini et al [24] proposed modifications of Snel et al [25] stall delay model empirical coefficients than studied the effect of the proposed modifications on the MEX-ICO rotor using the ADM implemented in OpenFOAM where a certain improvements has been noticed.…”