Geoffrey Andrews, Elizabeth Benitez and Paul Witsberger

Ph.D. students Geoffrey Andrews, Elizabeth Benitez and Paul Witsberger have been awarded the Purdue Forever Fellowship.

Each will receive a $5,000 scholarship. Only domestic Ph.D. students who passed qualifying exams were eligible to apply for the scholarship. The graduate committee reviewed applications and chose the fellowship recipients. The Purdue Forever Fellowship was made possible by the McAllister-Elrod family.

Andrews is studying hypersonic boundary layer transition under Jonathan Poggie, an associate professor in AAE. The area is difficult to study because the transition process from smooth (laminar) flow to turbulent (chaotic) flow is very sensitive to small irregularities. Andrews is studying the effects of those factors using large-scale computer simulations, with a special focus on the role of the ambient noise environment within wind tunnels. The will help to improve the data generated by existing wind tunnels and enable the development of viable hypersonic flight systems, such as high-speed transports and low-cost space access systems.

“The fellowship’s support makes life as a graduate student a little bit simpler and makes it easier for me to pursue other exciting opportunities at Purdue, such as earning my flight instructing certificate and practicing competition aerobatics,” said Andrews, whose master’s is from AAE. “Perhaps more importantly, being a student in the School of Aeronautics and Astronautics and having the opportunity to work with some of the best professors and students in the world is a privilege and I’m genuinely honored to be recognized amongst such lofty peers.”

Benitez’s research focuses on hypersonic instabilities generated or amplified by a separation bubble in the flow. Along with traditional surface measurements, she is using a focused laser differential interferometer that she developed to measure instabilities off-the-surface. Studying those instabilities is important because they may form on the control surfaces of hypersonic vehicles, and understanding the flow over such surfaces is essential for designing a controllable vehicle.

“I’m honored to be receiving this award for the second year,” said Benitez, who is co-advised by Professor Steven Schneider and Joseph Jewell, an assistant professor in AAE. “The Purdue Forever Fellowship has helped me to spend my time focused on my research rather than on finances, and I am grateful to be selected for this award.”

Witsberger’s research involves using machine learning to address the missed-thrust problem in interplanetary spacecraft design. Many trajectory design methods focus on finding trajectories that use as little propellant as possible, but little effort has been devoted to studying how robust those trajectories are to unforeseen problems that would cause the spacecraft to deviate from their planned course. Witsberger is using a neural network to create trajectories that are more robust to these events. He’s in Professor James Longuski’s research group.

“I am very grateful to the McAllister-Elrod family for their generosity, and I am humbled to have received this fellowship. This will allow me to focus more on my research and enable me to acquire better equipment,” said Witsberger (BSAAE ’16, MSAAE ’17).