Calibration of the 7—Equation Transition Model for High Reynolds Flows at Low Mach

Colonia, Simone; Leble, Vladimir; Steijl, R.; Barakos, George N.

doi:10.1088/1742-6596/753/8/082027

Cited by 7 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our implementation of the one-equation model uses modified coefficients of C TU1 , C TU2 , and C TU3 compared to that by Menter et al (2015), which gives better correlation with the experiments than the original values, as shown by Colonia et al (2016). The modified values of the constants are…”

Section: One-equation Laminar-turbulent Boundary Layer Transition Modelmentioning

confidence: 99%

Local correlation-based transition models for high-Reynolds-number wind-turbine airfoils

et al. 2022

View full text Add to dashboard Cite

Abstract. Modern wind-turbine airfoil design requires robust performance predictions for varying thicknesses, shapes, and appropriate Reynolds numbers. The airfoils of current large offshore wind turbines operate with chord-based Reynolds numbers in the range of 3–15 million. Turbulence transition in the airfoil boundary layer is known to play an important role in the aerodynamics of these airfoils near the design operating point. While the lack of prediction of lift stall through Reynolds-averaged Navier–Stokes (RANS) computational fluid dynamics (CFD) is well known, airfoil design using CFD requires the accurate prediction of the glide ratio (L/D) in the linear portion of the lift polar. The prediction of the drag bucket and the glide ratio is greatly affected by the choice of the transition model in RANS CFD of airfoils. We present the performance of two existing local correlation-based transition models – one-equation model (γ− SA) and two-equation model (γ-Reθt‾- SA) coupled with the Spalart–Allmaras (SA) RANS turbulence model – for offshore wind-turbine airfoils operating at a high Reynolds number. We compare the predictions of the two transition models with available experimental and CFD data in the literature in the Reynolds number range of 3–15 million including the AVATAR project measurements of the DU00-W-212 airfoil. Both transition models predict a larger L/D compared to fully turbulent results at all Reynolds numbers. The two models exhibit similar behavior at Reynolds numbers around 3 million. However, at higher Reynolds numbers, the one-equation model fails to predict the natural transition behavior due to early transition onset. The two-equation transition model predicts the aerodynamic coefficients for airfoils of various thickness at higher Reynolds numbers up to 15 million more accurately compared to the one-equation model. As a result, the two-equation model predictions are more comparable to the predictions from eN transition model. However, a limitation of this model is observed at very high Reynolds numbers of around 12–15 million where the predictions are very sensitive to the inflow turbulent intensity. The combination of the two-equation transition model coupled with the Spalart–Allmaras (SA) RANS turbulence model is a good method for performance prediction of modern wind-turbine airfoils using CFD.

show abstract

Section: One-equation Laminar-turbulent Boundary Layer Transition Modelmentioning

confidence: 99%

Local correlation-based transition models for high-Reynolds-number wind-turbine airfoils

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Our implementation of the one-equation model uses modified coefficients of C T U 1 , C T U 2 , and C T U 3 compared to that by Menter et al (2015), which gives better correlation with the experiments than the original values, as shown by Colonia et al (2016). The modified values of the constants are…”

Section: One-equation Laminar-turbulent Boundary Layer Transition Modelmentioning

confidence: 99%

Local Correlation-based Transition Models for High-Reynolds-Number Wind Turbine Airfoils

Jung

Vijayakumar

Ananthan

et al. 2021

Preprint

View full text Add to dashboard Cite

Abstract. Modern wind-turbine airfoil design requires robust performance predictions for varying thicknesses, shapes, and appropriate Reynolds numbers. The airfoils of current large offshore wind turbines operate with chord-based Reynolds numbers in the range of 3–15 million. Turbulence transition in the airfoil boundary layer is known to play an important role in the aerodynamics of these airfoils near the design operating point. While the lack of prediction of lift stall through Reynold-averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) is well-known, airfoil design using CFD requires the accurate prediction of the glide ratio (L / D) in the linear portion of the lift polar. The prediction of the drag bucket and the glide ratio is greatly affected by the choice of the transition model in RANS-CFD of airfoils. We present the performance of two existing local correlation-based transition models – one-equation (γ) and two-equation model coupled with the Spalart-Allmaras (SA) RANS turbulence model – for offshore wind-turbine airfoils operating at a high Reynolds number. We compare the predictions of the two transition models with available experimental and CFD data in the literature in the Reynolds number range of 3–15 million including the AVATAR project measurements of the DU00-W-212 airfoil. Both transition models predict a larger L / D compared to fully turbulent results at all Reynolds numbers. The two models exhibit similar behavior at Reynolds numbers around 3 million. However, at higher Reynolds numbers, the one-equation model fails to predict the natural transition behavior due to early transition onset. The two-equation transition model predicts the aerodynamic coefficients for airfoils of various thickness at higher Reynolds numbers up to 15 million more accurately compared to the one-equation model. The two-equation model also predicts the correct trends with the variation of Reynolds number comparable to the eN transition model. However, a limitation of this model is observed at very high Reynolds numbers of around 12–15 million where the predictions are very sensitive to the inflow turbulent intensity. The combination of the transition model coupled with the Spalart-Allmaras (SA) RANS turbulence model is a robust method for performance prediction of modern wind-turbine airfoils using CFD.

show abstract

CFD Simulations for Airfoil Polars

Sezer-Uzol¹,

Uzol²,

Orbay-Akcengiz³

2021

Handbook of Wind Energy Aerodynamics

View full text Add to dashboard Cite

Calibration of the 7—Equation Transition Model for High Reynolds Flows at Low Mach

Cited by 7 publications

References 14 publications

Local correlation-based transition models for high-Reynolds-number wind-turbine airfoils

Local correlation-based transition models for high-Reynolds-number wind-turbine airfoils

Local Correlation-based Transition Models for High-Reynolds-Number Wind Turbine Airfoils

CFD Simulations for Airfoil Polars

Contact Info

Product

Resources

About