Wind Turbine Performance in Controlled Conditions: BEM Modeling and Comparison with Experimental Results

Abstract

Predictions of the performance of operating wind turbines are challenging for many reasons including the unsteadiness of the wind and uncertainties in blade aerodynamic behaviour. In the current study an extended blade element momentum (BEM) program was developed to compute the rotor power of an existing 4.3 m diameter turbine and compare predictions with reported controlled experimental measurements. Beginning with basic blade geometry and the iterative computation of aerodynamic properties, the method integrated the BEM analysis into the program workflow ensuring that the power production by a blade element agreed with its lift and drag data at the same Reynolds number. The parametric study using the extended BEM algorithm revealed the close association of the power curve behaviour with the aerodynamic characteristics of the blade elements, the discretization of the aerodynamic span, and the dependence on Reynolds number when the blades were stalled. Transition prediction also affected overall performance, albeit to a lesser degree. Finally, to capture blade finite area effects, the tip loss model was adjusted depending on stall conditions. The experimental power curve for the HAWT of the current study was closely matched by the extended BEM simulation.

A compact in-blade five hole pressure probe for local inflow study on a horizontal axis wind turbine

“…Compared to other wind tunnels this facility presents an intentional relatively high turbulence intensity (between 5.9% to 6.2% (Gertz et al, 2012; Johnson et al, 2012)) and, due to the low flow blockage ratio, this is a good resemblance of realistic flow conditions for wind turbines during actual operations. Detailed wind velocity measurements at the location where the wind turbine is installed, as well as flow characterization, can be found in Gertz et al (2012); Johnson et al (2012) and Johnson and Gaunt (2012).…”

Design, Manufacturing and Testing of Inversed Taper NACA 4412 Airfoil with Blade Made of Hybrid Empty Fruit Bunch Bio-composites

“…This parameter is commonly known as the power coefficient and where the max Cp = 0.593, it is referred to as the Betz limit [25]. In order to effectively model the performance of the wind turbine, the geometry of the blades produced is determined by the chord, twist, and airfoil [26]. Input parameters should be identified for the design, such as several variables that are calculated and determined in the initial steps of designing the wind turbine blades, as shown in Table 1.…”

Modelado y simulación de un aerogenerador de 5 MW escalado a partir de uno de 7 KW

“…Tanto como ' son factores de aprovechamiento de la velocidad del viento a nivel del rotor. Figura 1: Triángulo de velocidades para una sección de pala [6].…”