Research
Wind Turbine Aerodynamics and Interactions
Wind turbine research at Aerodynamics and Wind Energy Lab (AWEL) is motivated by a desire to better understand flow physics that drive energy generation in both steady and unsteady conditions. Previous turbine testing has been conducted at the High Reynolds Number Testing Facility (HRTF) at Princeton University, a facility capable of matching operational conditions of full scale wind turbines via pressurization. The HRTF allows for relatively low cost tests in comparison to simulations and in-field experiments. The turbine prototypes were mounted to a measurement and control stack containing a load cell, yaw stage, and a torque transducer, which were then loaded into the HRTF for turbine performance data collection. Effects of yaw angle and tip speed ratio at a variety of flow speeds on turbine performance metrics such as thrust and power were revealed for the first time at field-relevant operational conditions. In the wind energy community, manipulation of the yaw angle in self-starting and free-spinning turbines is a novel area of research, with the research conducted at AWEL providing critical insight into effects of realistic wind conditions on turbine performance.
Future testing is planned at the Optical Towing Tank for Energetics Research (OTTER) facility, with the goal of venturing into unsteady aerodynamics. Additional testing to determine how yaw angle can affect fan speed and tip speed ratio is currently planned, with specific focus on operation under yaw misalignment. The OTTER facility will be instrumented to test flow conditions for straight and yawed turbines subject to steady winds, as well as wind gusts. This will be accomplished through the development of a scaled down Model Wind Turbine (MoWiTo) prototype.
Status: Active
Students: Aidan Westdal
Collaborators: Supun Pieris, John W. Kurelek
Wind Assisted Ship Propulsion
Rotor sails are slender cylindrical structures mounted on ships that aid in propulsion through forces generated using the Magnus effect. Previous testing of rotor sails has been conducted at low Reynolds numbers, however on large transport ships, the Reynolds number can exceed 3.5 million. The objective of this study was to characterize the effects of Reynolds number, velocity ratio, and tip effects on aerodynamic loading of a single rotor at full dynamic similarity. Testing was conducted within a High Reynolds Number Test Facility (HRTF) at Princeton University, a world unique facility that can be pressurized at up to 3500 psi for operational Reynolds numbers to be achieved. Three different rotor sail models with varying aspect ratios and endplates were tested, revealing previously unknown aerodynamic behaviour of rotor sails.
The experiment successfully developed a proof of concept for testing rotor sail diagnostics at a field-relevant Reynolds number. The results from the testing determined that increasing velocity ratio lead to increased performance The effect of endplates were found to be the most impactful sail design characteristic as well, with larger endplates generating higher loads at higher velocity ratios. These tests served as an extremely useful validation dataset for rotor sail performance, in an effort to better study the positive environmental impact of rotor sails. Rotor sails have the ability to make a significant impact on decarbonization of the maritime industry, and through creating an aerodynamic model at full dynamic similarity, a strong foundation is laid for future research. The research group hopes to expand our understanding of rotor sail aerodynamics through further simulations and experiments at operational conditions. Additional testing into flow measurement and implementation of a pressure sensing system is planned to be implemented in the future.
Status: Active
Students: Katie Cooper-Gray, Aidan Westdal
Collaborators: Supun Pieris, John W. Kurelek
Facilities
Optical Towing Tank for Energetics Research (OTTER)
The Optical Towing Tank for Energetics Research (OTTER) is a testing facility located in McLaughlin Hall at Queen’s University. Acquired from the National Research Council of Canada (NRC) in 2014, the facility is designed for high Reynolds number testing with applications in aerospace, defence, and renewable technologies. Although models are scaled down in size, the use of water over air in a wind tunnel allows for higher Reynolds numbers to be reached. Submerged models move by a motorized carriage system across the 15 m length of the tow tank, with a 1 m by 1 m cross-section capable of reproducing both steady and dynamic flow conditions through carriage motion. The models may be instrumented to record force and surface pressures, and can be further manipulated (e.g., pitching and surging of an airfoil) during their motion. Optical flow measurements, such as particle image velocimetry (PIV), are also possible using cameras and lasers mounted on two other traverse systems beside and below the facility, that are synchronized to the model motion. These results facilitate wake analysis behind the towed model, and combined with simultaneous model force and pressure measurements, allow for better understanding of the underlying flow physics.
OTTER has been utilized within our research group for many different testing purposes, most notably for wind turbine and solar panel research projects. The facility has been used to test turbines, airfoils, and flat plate models when exposed to unsteady aerodynamic conditions at high Reynolds numbers, such as change in wind direction or speed. OTTER is currently undergoing upgrades to its propulsion system with the goal of being able to safely reach higher towing speeds and accelerations.
Status: Active
Students: Aidan Westdal
Collaborators: Supun Pieris, John W. Kurelek