Mechanical Engineering Commons^™

Acausal Modeling Of Wind Turbines With Validation And Control Studies, Kazi Ishtiak Mohsin

Graduate Thesis and Dissertation 2023-2024

This thesis involves the modeling, validation, and control studies of a Control-Oriented, Reconfigurable, and Acausal Floating Turbine Simulator (CRAFTS), that is currently under development. CRAFTS uses Modelica®, an object-oriented, declarative, multi-domain modeling language for physical system modeling in the Dymola environment. The CRAFTS simulator facilitates rapid dynamic simulation of wind turbines with various model variants and enables control co-design.

A major emphasis of this thesis is in the validation of the CRAFTS simulator for a 15-MW land-based wind turbine through several test cases. These test cases were collaboratively developed in conjunction with other participating research entities. CRAFTS has undergone rigorous …

Wind Blade Manufacturing For The Cal Poly Wind Power Club, Benjamin E. Thompson, Jake R. Lund, Claudia C. Angeles

Mechanical Engineering

The Cal Poly Wind Power Club is entering the 2021 Collegiate Wind Competition (CWC) in June. Last year, three senior project teams were assigned to collaborate and assist the club with the pitching mechanism, the rotor balancing, and the manufacturing process. As the manufacturing team, the goal of our project was to design a manufacturing process for the bladegeometry given. The manufacturing process was required to meet the team’s expectations and CWC’s performance requirements to place highly in the competition taking place in June 2021.These expectations included creating a manufacturing process that is repeatable and reliable for future competitions. The …

Measurements Of Wind Turbine Wake Evolution And Trajectory During Morning Boundary Layer Transition And Under Wake Steering Conditions Via Unmanned Aerial Vehicles, Stewart Nelson

Theses and Dissertations--Mechanical Engineering

In July of 2019, a flight campaign was conducted using semi-autonomous Unmanned Aerial Vehicles (UAVs) at the Port Alma Kruger Energy wind farm in Ontario, Canada, to study various aspects of wind turbine wake evolution. Horizontal transects across the wakes were measured using modified fixed-wing aircraft fitted with a five-hole probe to measure the wind velocity vector. Reference boundary layer conditions were measured by an octocopter with an assortment of mounted sensors flying vertical profiles upstream of the turbines. Three experiments were conducted during the campaign, which consisted of a study on wake behavior during the morning boundary layer transition, …

Considerations For The Design Optimization Of Floating Offshore Wind Turbine Blades, Evan M. Gaertner

Doctoral Dissertations

Floating offshore wind turbines are an immature technology with relatively high costs and risk associated with deployment. Of the few floating wind turbine prototypes and demonstration projects deployed in real metocean conditions, all have used standard turbines design for onshore or offshore fixed bottom conditions. This neglects the unique unsteady aerodynamics brought on by floating support structure motion. While the floating platform has been designed and optimized for a given rotor, the global system is suboptimal due to the rotor operating in conditions outside of which it was design for. If the potential offered by floating wind turbines is to …

Design And Testing Of A Wind Energy Harnessing System For Forced Convective Drying Of Grain In Low Wind Speed, Warm And Humid Climates, Francis Akumabi Agbali

Theses and Dissertations--Biosystems and Agricultural Engineering

Forced convective drying using a wind turbine mechanically connected to a ventilation fan was hypothesized for low cost and rapid grain drying in developing countries. The idea was tested using an expandable wind turbine blade system with variable pitch, at low wind speeds in a wind tunnel. The design was based on empirical and theoretical models embedded in a graphical user interface (GUI) created to estimate airflow-power requirements for drying ear corn. Output airflow (0.0016 - 0.0052 m³kg^-1s^-1) increased within the study wind speed range (2.0 - 5.5 m/s). System efficiency peak (8.6%) was …

Analysis Of The Properties Of Supercapacitors And Possible Applications For The Technology, Vincent Oliveto

Honors Theses

Supercapacitors have a lot of excellent qualities that would make them a great substitute for batteries when it comes to electrical energy storage systems. Supercapacitors can discharge and charge very rapidly, they have a lifespan in the realm of millions of cycles, and they are much more efficient than batteries. Unfortunately, they cannot hold nearly as much charge as batteries. This paper seeks to further investigate the properties of supercapacitor technology and the best way to exploit these properties with the purpose of integrating them into renewable energy systems. There is currently a lot of research occurring around the world …

Automated Cfd Optimization To Maximize Wind Farms Performance And Land Use, Rafael Valotta Rodrigues

Electronic Theses and Dissertations

In this research, a computational system was designed to analyze and optimize the layout of wind farms under variable operational conditions. At first, a wind turbine computational fluid dynamic (CFD) model was developed covering the near wake. The near wake flow field was validated against near wake velocity data from the MEXICO experiment. The CFD simulation demonstrated that the tip speed ratio and the pitch angle greatly influence the near wake behavior, affecting the velocity deficit and the turbulence intensity profile in this region. The CFD model was extended to cover the far wake, aiming to become a computational tool …

Improving The Efficiency Of Wind Farm Turbines Using External Airfoils, Shujaut Bader

Masters Theses

Wind turbine efficiency typically focuses on the shape, orientation, or stiffness of the turbine blades. In this thesis, the focus is instead on using static fixed airfoils in proximity to the wind turbine to control the airflow coming out of the turbine. These control devices have three beneficial effects. (1) They gather air from “higher up” where the air is moving faster on average (and therefore has more kinetic energy in it). (2) They throw the used (and slowed down air) downwards. This means that any turbines in the wind farm behind the lead turbines do not get “stale” air. …

Analysis Of Aeroelastic Effects On The 3-Dimensional Interference Of Wind-Turbine Rotors, Anurag Rajan

Dissertations, Master's Theses and Master's Reports

Greater penetration of wind energy demands better utilization of available wind. This has led to a formidable increase in the rotor diameter over the past few years. Bigger rotors call for lighter, more flexible blades to reduce loads and improve fatigue life. As a result, future blades will deform substantially more than the relatively stiff blades of the past. More efficient use of wind power also calls for incorporating advanced active and passive control strategies and increasing the range of velocities over which wind energy is captured. Hence an improvement in the quality of numerical simulations capable of capturing the …

The Role Of Active Flow-Control Devices In The Dynamic Aeroelastic Response Of Wind Turbine Rotors, Muraleekrishnan Menon Menon Muraleedharan Nair

Dissertations, Master's Theses and Master's Reports

The significance of wind as a renewable source of power is growing with the increasing capacity of individual utility-scale wind turbines. Contemporary wind turbines are capable of producing up to 8 MW and consequently, their rotor sizes are rapidly growing in size. This has led to an increased emphasis on studies related to improvements and innovations in load-control methodologies. Most often than not, controlling the loads on an operational turbine is a precarious scenario, especially under high wind loading. The up-scaling of turbine rotors would thus benefit from a rationale change in load control through methodologies such as variable-speed stall, …

Aerodynamic And Modal Analyses Of Small Scale Horizontal Axis Wind Turbine With Various Numbers Of Blade Design, Emile Maroha

Electronic Theses and Dissertations

With the global energy demand rising to unprecedented numbers, the need for alternative energy sources is ever prevalent. Wind energy is the most alternative renewable sources today due to its year-round availability and pollution-free nature. Horizontal Axis Wind Turbines (HAWT) are the most popular because of their higher efficiency. The aerodynamic characteristics and vibration of small scale HAWT with various numbers of blade design have been investigated in this numerical study in order to improve its performance. SolidWorks was used for designing CAD models, and ANSYS software was used to study the dynamic flow around the turbine as well as …

Cfd Simulation Of The Flow Around Nrel Phase Vi Wind Turbine, Yang Song

Masters Theses

The simulation of the turbulent and potentially separating flow around a rotating, twisted, and tapered airfoil is a challenging task for CFD simulations. This thesis describes CFD simulations of the NREL Phase VI turbine that was experimentally characterized in the 24.4m X 36.6m NREL/NASA Ames wind tunnel. All computations in this research are performed on the experimental base configuration of 0^o yaw angle, 3^o tip pitch angle, and a rotation rate of 72 rpm. The significance of specific mesh resolution regions to the accuracy of the CFD prediction is discussed. The ability of CFD to capture bulk quantities, …

An Experimental Investigation Of Wind Turbine Aerodynamic Interaction, Brandon Lee Ennis

Open Access Dissertations

Wind turbines have become a viable component in the overall energy makeup of the United States due to improved economics where energy prices have risen and production costs dropped. For a fixed cost, the effectiveness of a wind turbine financially is highly related to its performance. Considering the size of current wind farms, a minor performance improvement will result in large additional sums of revenue. A problem that has received attention with wind farms is that while the fixed costs of the development do get spread out further to reduce the installed cost of each wind turbine, the wind turbines …

Rotor Blade Operational Data Analysis Methods And Applications For Health Monitoring Of Wind Turbines Using Integrated Blade Sensing, Noah Jacob Myrent

Open Access Theses

Wind energy is one of the fastest growing sources of power production in the world today. In order to extract the maximum potential amount of energy from the wind, a wind turbine's reliability must be a top priority. As utility scale wind turbines increase in size and initial capital investment cost, there also comes an increasing need to monitor the health of the turbine. Currently, most wind turbines do not incorporate blade mounted inertial sensing in addition to blade strain measurements. This approach has the potential to detect inevitable blade damage types early on so that a maintenance schedule can …

Static Balancing Of The Cal Poly Wind Turbine Rotor, Derek Simon

Master's Theses

The balancing of a wind turbine rotor is a crucial step affecting the machine’s performance, reliability, and safety, as it directly impacts the dynamic loads on the entire structure.

A rotor can be balanced either statically or dynamically. A method of rotor balancing was developed that achieves both the simplicity of static balancing and the accuracy of dynamic balancing. This method is best suited, but not limited, to hollow composite blades of any size. The method starts by quantifying the mass and center of gravity of each blade. A dynamic calculation is performed to determine the theoretical shaking force on …

The Effect Of Magnetic Bearing On The Vibration And Friction Of A Wind Turbine, Mark Ryan Vorwaller

Electronic Theses and Dissertations

Demands for sustainable energy have resulted in increased interest in wind turbines. Thus, despite widespread economic difficulties, global installed wind power increased by over 20% in 2011 alone. Recently, magnetic bearing technology has been proposed to improve wind turbine performance by mitigating vibration and reducing frictional losses. While magnetic bearing has been shown to reduce friction in other applications, little data has been presented to establish its effect on vibration and friction in wind turbines. Accordingly, this study provides a functional method for experimentally evaluating the effect of a magnetic bearing on the vibration and efficiency characteristics of a wind …

Boundary Layer Data System (Blds) Heating System, John Hauge, Drew Hutcheson, Paul Scott

Mechanical Engineering

The boundary layer data system (BLDS) is the result of a collaborative effort between Dr. Westphal, a researcher and instructor at Cal Poly, and Northrop Grumman. The BLDS is capable of measuring the boundary layer profile and characteristics of flow over aerodynamic surfaces and is intended for high altitude, high speed use. The instruments inside the BLDS malfunction at the low temperatures present when operating in flight at altitudes above 30,000 ft. To solve this problem, analysis was done on the existing BLDS which determined the heating requirements, around 50 watts, needed to keep the internal temperature within the rated …