Accuracy of the Gamma Re-Theta Transition Model for Simulating the DU-91-W2-250 Airfoil at High Reynolds Numbers

Abstract

Accurate computation of the performance of a horizontal-axis wind turbine (HAWT) using Blade Element Momentum (BEM) based codes requires good quality aerodynamic characteristics of airfoils. This paper shows a numerical investigation of transitional flow over the DU 91-W2-250 airfoil with chord-based Reynolds number ranging from 3 × 106 to 6 × 106. The primary goal of the present paper is to validate the unsteady Reynolds averaged Navier-Stokes (URANS) approach together with the four-equation transition SST turbulence model with experimental data from a wind tunnel. The main computational fluid dynamics (CFD) code used in this work was ANSYS Fluent. For comparison, two more CFD codes with the Transition SST model were used: FLOWer and STAR-CCM +. The obtained airfoil characteristics were also compared with the results of fully turbulent models published in other works. The XFOIL approach was also used in this work for comparison. The aerodynamic force coefficients obtained with the Transition SST model implemented in different CFD codes do not differ significantly from each other despite the different mesh distributions used. The drag coefficients obtained with fully turbulent models are too high. With the lowest Reynolds numbers analyzed in this work, the error in estimating the location of the transition was significant. This error decreases as the Reynolds number increases. The applicability of the uncalibrated transition SST approach for a two-dimensional thick airfoil is up to the critical angle of attack.

Preliminary assessment of the NACA0021 trailing edge wedge for wind turbine application

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Unstable tilt-rotor maximum likelihood wavelet-based identification from flight test data

“…Berger et al (2020) and Olsson et al (2021); wind tunnel test and computational fluid dynamics (CFD) outcomes verification, e.g. Murphy et al (2011) and Michna et al (2019); control law design and handling qualities assessment, e.g. Cho et al (2019) and Schulze et al (2019); flight envelop expansion during prototype testing, e.g.…”

“…wind tunnel test and computational fluid dynamics (CFD) outcomes verification, e.g. Murphy et al (2011) and Michna et al (2019);…”

Numerical simulation of the aerodynamic characteristics of the NACA 0018 airfoil at medium range Reynolds number

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