The Effect of Various Actuator-Line Modeling Approaches on Turbine-Turbine Interactions and Wake-Turbulence Statistics in Atmospheric Boundary-Layer Flow

Conference · Mon Jan 13 04:00:00 EST 2014

DOI:https://doi.org/10.2514/6.2014-0710· OSTI ID:1348925

Jha, Pankaj ^[1]; Churchfield, Matthew ^[2]; Moriarty, Patrick ^[2]; Schmitz, Sven ^[3]

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1. Pennsylvania State Univ., University Park, PA (United States); Department of Aerospace Engineering, Pennsylvania State University
2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
3. Pennsylvania State Univ., University Park, PA (United States)

When using an actuator-line representation of a wind turbine for computational fluid dynamics, it is common practice to volumetrically project the line force onto the flow field to create a body force in the fluid momentum equation. The objective of this study is to investigate how different volumetric projection techniques of the body force created by an actuator-line wind turbine rotor model affect the generated wake characteristics and blade loads in a turbine-turbine interaction problem. Two techniques for the body-force projection width are used , and they are based on either i) the grid spacing, or ii) the combination of grid spacing and an equivalent elliptic blade planform. An array of two NREL 5-MW turbines separated by seven rotor diameters is simulated within a large-eddy simulation solver subject to offshore neutral and moderately-convective atmospheric boundary-layer inflow. Power, thrust,and bending moment histories of both turbines, the statistics of angle of attack and blade loads over 2000 sec, variations in the mean and fluctuating velocity components, and turbulent kinetic energy and selected Reynolds stresses along vertical and spanwise sampling locations in the wake are analyzed. Comparisons for the different techniques of determining the body-force projection width of the actuator-line method are made and their effect on different physical quantities are assessed.

• Research Organization: Pennsylvania State Univ., University Park, PA (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Wind and Water Technologies Office (EE-4W)
• DOE Contract Number: EE0005481
• OSTI ID: 1348925
• Report Number(s): AIAA-2014--0710
• Country of Publication: United States
• Language: English

Related Subjects

Atmospheric boundary layer
wind turbine wake
wind energy