OUR AMA ZING FACILITIES
Unique facility for the
PhD candidate Jaime Wong peers into the towing tank.
B
irds, insects and fish—past and present—have evolved to be remarkably efficient in moving and manoeuvring through air and water. The new OTTER (Optical Towing Tank for Energetics Research) lab, located in McLaughlin Hall, allows aerodynamics and hydrodynamics researchers to study, through hightech experiments, how flying creatures like seagulls and dragonflies move, accelerate, reverse direction and outmanoeuvre any aircraft designed by humans.
“Nature has optimized propulsion in air and water in many different ways,” says Dr. David Rival, OTTER lab supervisor and an assistant professor in the Queen’s Department of Mechanical and Materials Engineering. “Our research focuses on learning from nature to develop engineering solutions for contemporary societal problems, such as using wind energy more efficiently and making aerospace technology cleaner to reduce greenhouse gas emissions. Because of its unique construction, the optical towing tank allows us to test the aerodynamics of models at speeds and scales relevant to industrial applications.” The OTTER facility is a 15-metre-long glass tank, holding approximately 15 tons of water. As fully submerged models— abstract representations of the animals— are towed rapidly through the tank, its
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THE COMPLETE ENGINEER
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high-speed lasers and cameras visualize, reconstruct and measure the flow fields around them in three dimensions. Through
In nature, seagulls and
dragonflies have evolved much better ways of
extracting the wind’s energy...
such experiments, the researchers can analyze the aerodynamic performance of these models in terms of propulsive efficiency and manoeuvrability, which provides new insights and ideas for improving the efficiency of, for instance, wind turbines and turbofan engines for the
aerospace industry. Dr. Rival’s group uses the OTTER lab as a tool to help improve the performance and longevity of wind turbines in gusty conditions. In nature, seagulls and dragonflies have evolved much better ways of extracting the wind’s energy for their benefit in unsteady airflows. The team runs experiments to simulate the responses of seagulls and scaled wind turbine models to such uneven flows. “By towing the model, we can create the effect of a gust hitting a turbine blade by accelerating the blade through the tank. We feed back what we learn into the design and siting of turbines to optimize their operation in an unsteady environment,” he explains. The lab’s leading-edge experimental equipment is a huge hit with students like Jaime Wong, a PhD candidate in
