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Simulation and modeling of flow field around a horizontal axis wind turbine (HAWT) using RANS method
Title
Simulation and modeling of flow field around a horizontal axis wind turbine (HAWT) using RANS method.
Creator
Sargsyan, Armen., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
The principal objective of the proposed CFD analysis is to investigate the flow field around a horizontal axis wind turbine rotor and calculate the turbine's power. A full three dimensional computational fluid dynamics method based on Reynolds Averaged Navier Stokes approach was used in this study. The wind turbine has three blades and a rotor diameter of six meters. One third of the wind turbine rotor was modeled by means of 120o periodicity in a moving reference frame system. The power...
Show moreThe principal objective of the proposed CFD analysis is to investigate the flow field around a horizontal axis wind turbine rotor and calculate the turbine's power. A full three dimensional computational fluid dynamics method based on Reynolds Averaged Navier Stokes approach was used in this study. The wind turbine has three blades and a rotor diameter of six meters. One third of the wind turbine rotor was modeled by means of 120o periodicity in a moving reference frame system. The power coefficient curve obtained from the CFD results is compared with experimental data obtained by NREL Phase VI rotor experiment. The numerical result for the power coefficient curve shows close agreement with the experimental data. The simulation results include the velocity distribution, pressure distribution along the flow direction, turbulent wake behind the wind turbine, and the turbine's power. The discussion will also include the effect of wind speed on turbine's power.
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Date Issued
2010
PURL
http://purl.flvc.org/FAU/2979383
Subject Headings
Wind turbines, Aerodynamics, Computer simulation, Fluid dynamics, Computational methods, Vibration (Aerodynamics)
Format
Document (PDF)
Developing interpretive turbulence models from a database with applications to wind farms and shipboard operations
Title
Developing interpretive turbulence models from a database with applications to wind farms and shipboard operations.
Creator
Schau, Kyle A., Gaonkar, Gopal H., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
This thesis presents a complete method of modeling the autospectra of turbulence in closed form via an expansion series using the von Kármán model as a basis function. It is capable of modeling turbulence in all three directions of fluid flow: longitudinal, lateral, and vertical, separately, thus eliminating the assumption of homogeneous, isotropic flow. A thorough investigation into the expansion series is presented, with the strengths and weaknesses highlighted. Furthermore, numerical...
Show moreThis thesis presents a complete method of modeling the autospectra of turbulence in closed form via an expansion series using the von Kármán model as a basis function. It is capable of modeling turbulence in all three directions of fluid flow: longitudinal, lateral, and vertical, separately, thus eliminating the assumption of homogeneous, isotropic flow. A thorough investigation into the expansion series is presented, with the strengths and weaknesses highlighted. Furthermore, numerical aspects and theoretical derivations are provided. This method is then tested against three highly complex flow fields: wake turbulence inside wind farms, helicopter downwash, and helicopter downwash coupled with turbulence shed from a ship superstructure. These applications demonstrate that this method is remarkably robust, that the developed autospectral models are virtually tailored to the design of white noise driven shaping filters, and that these models in closed form facilitate a greater understanding of complex flow fields in wind engineering.
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Date Issued
2013
PURL
http://purl.flvc.org/fau/fd/FA0004058
Subject Headings
Fluid mechanics, Renewable energy sources, Von Kármán, Theodore -- 1881-1963, Wind energy conservation systems, Wind power, Wind turbines -- Aerodynamics
Format
Document (PDF)
Numerical Simulation of an Ocean Current Turbine Operating in a Wake Field
Title
Numerical Simulation of an Ocean Current Turbine Operating in a Wake Field.
Creator
Pyakurel, Parakram, VanZwieten, James H., Dhanak, Manhar R., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
An Ocean Current Turbine (OCT) numerical simulation for creating, testing and tuning flight and power takeoff controllers, as well as for farm layout optimization is presented. This simulation utilizes a novel approach for analytically describing oceanic turbulence. This approach has been integrated into a previously developed turbine simulation that uses unsteady Blade Element Momentum theory. Using this, the dynamical response and power production of a single OCT operating in ambient...
Show moreAn Ocean Current Turbine (OCT) numerical simulation for creating, testing and tuning flight and power takeoff controllers, as well as for farm layout optimization is presented. This simulation utilizes a novel approach for analytically describing oceanic turbulence. This approach has been integrated into a previously developed turbine simulation that uses unsteady Blade Element Momentum theory. Using this, the dynamical response and power production of a single OCT operating in ambient turbulence is quantified. An approach for integrating wake effects into this single device numerical simulation is presented for predicting OCT performance within a farm. To accomplish this, far wake characteristics behind a turbine are numerically described using analytic expressions derived from wind turbine wake models. These expressions are tuned to match OCT wake characteristics calculated from CFD analyses and experimental data. Turbine wake is characterized in terms of increased turbulence intensities and decreased mean wake velocities. These parameters are calculated based on the performance of the upstream OCT and integrated into the environmental models used by downstream OCT. Simulation results are presented that quantify the effects of wakes on downstream turbine performance over a wide range of relative downstream and cross stream locations for both moored and bottom mounted turbine systems. This is done to enable the development and testing of flight and power takeoff controllers designed for maximizing energy production and reduce turbine loadings.
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Date Issued
2016
PURL
http://purl.flvc.org/fau/fd/FA00004737, http://purl.flvc.org/fau/fd/FA00004737
Subject Headings
Turbulence--Mathematical models., Marine turbines--Mathematical models., Wind turbines--Aerodynamics--Mathematical models., Structural dynamics., Computational fluid dynamics., Fluid dynamic measurements., Atmospheric circulation.
Format
Document (PDF)