AE’s Pomeroy Wins AIAA Orville and Wilbur Wright Graduate Award

Brent Pomeroy knew as an undergrad at Clarkson University in upstate New York that his life’s work would involve understanding the complexities of flight.

“I studied under Prof. Ken Visser, who had such a profound impact upon me going to grad school. He suggested (Aerospace Engineering at) Illinois, and I credit him with getting me involved with aerodynamics, a love of airplanes, and research as a whole,” Pomeroy said.

That keen interest has led Pomeroy, under the technical guidance of AE at Illinois Prof. Michael Selig, to conduct a unique doctoral study on the effect of high-lift aerodynamic flow fields on airplane wing flaps. It has led him to share his passion by creating within the department curriculum that encourages undergrads to get involved with research. And it has further led to his work with the Graduate Student Advisory Committee (GSAC) to improve the experience for his fellow graduate students.

Pomeroy’s efforts have earned for him the 2015 Orville and Wilbur Wright Graduate Award, one of the top graduate honors that the American Institute of Aeronautics and Astronautics (AIAA) presents annually to two outstanding graduate students.

“To put it plainly, Brent is one of the best and most engaged graduate students that our PhD program has been fortunate to attract over the past decade,” said AE Department Head Philippe Geubelle.

Working with Selig, Pomeroy wants to understand burst wakes that airplane wing flaps can create. The wakes can detrimentally impact the efficiency of takeoff and landing. Burst wakes increase the drag and decrease the lift of an airplane wing (or airfoil), Pomeroy said.  “This is not a good combination. As a designer, you never want to increase the drag and decrease the lift.

“If the adverse pressure gradients caused by the flaps is too great, the wakes may separate from themselves,” Pomeroy explained. “My research seeks to understand and determine the performance limits of these flaps. My project will impact the design of high-lift systems, as aircraft designers will have a clearer understanding of the limits of the design envelope and will be able to design more aggressive high-lift systems to decrease aircraft weight, simplify the high-lift system, reduce fuel burn, and yield less acoustic noise on takeoff.”

Pomeroy is gaining insight by comparing wind tunnel experiments to computer simulations. “For a variety of reasons, it’s very difficult to compare predictions from a computer simulation to an experiment for the flow field I am studying. There are always discrepancies between the computations and the experiment, and one may get two different answers from each tool. I am seeking to understand and quantify the differences between the computational simulations and experimental tests in an effort to understand exactly how much lift and drag is being produced by the high-lift system.”

Unique in Pomeroy’s research will be a never-done-before study of continuous measurements, rather than a point-by-point examination. “I’m taking measurements all along the flaps and burst wakes to understand the development of the flow field, in particular the development of the wakes, both in the simulations and in the wind tunnel,” he said. “It’s very hard to capture experimentally because it’s hard to physically access some of the points at which data need to be taken. In addition, some of these tests have been 14 hours of continuous data taking.”

Among aspects that he considers are:

• High-lift aerodynamics and design of high-lift systems
• Complex unsteady flows, with air constantly moving in unpredictable patterns, creating turbulence that is chaotic and difficult to capture in a wind tunnel and difficult to predict computationally
• Confluent boundary layers over each part of the wing. While the surface air moves at zero velocity, the outside air moves at full speed. The region between the two is difficult to predict and measure.
• Relating all the phenomena to optimized wing design.

Pomeroy was quick to credit Selig for the technical mentorship and guidance he has provided since he began advising Pomeroy in 2010. “Prof. Selig has provided invaluable advice regarding topics of applied aerodynamics and high-lift flow fields as well as introducing me to complex design routines.”

Even though most of Pomeroy’s research interests center on airplanes, wings, and airfoils, his investigations can be extended to other technical fields, such as wind energy and auto racing. As part of a five-person team, Pomeroy helped research and design a new large-scale wind turbine that utilized high-lift systems to create a more-efficient 10-MW scale wind turbine.

This summer, Pomeroy continues to develop his technical design abilities as an Aerodynamic Engineer at Boeing’s Advanced Concepts Design Center in Long Beach, California. He plans to complete his doctoral work in another year, and the Graduate College at Illinois has awarded him a Dissertation Completion Fellowship toward that goal.

Pomeroy also was fortunate to have earned a National Science Foundation (NSF) Fellowship when he began his graduate work at Illinois in 2010.

While pursuing his own research, Pomeroy over the past year also successfully developed within AE a sophomore-level, one-hour credit course to encourage undergraduates to do a research project over the length of a semester.

Undergrads in the initial offering this past spring worked closely with a postdoctoral research associate or senior graduate student on a project involving a literature review, a hands-on component, and a poster presentation. In addition, the undergrads participated in several workshops focused on various aspects of research. The students are encouraged to join a research group during their junior and senior years.

The 10 undergraduates in the class attended the AIAA Region 3 Student Paper Competition, presenting three papers at the conference. Conducting research stemming from Pomeroy’s larger project, undergraduate Aaron Perry of Omaha, Nebraska, placed second in the conference undergraduate category for his paper, “Geometric Effects on the Performance and Wake Development of a Multielement Airfoil System.”

Using MSES, a computational fluid dynamics code, Perry investigated how the airplane flap geometric arrangement affects the growth of the wing’s wake. He found that increasing the gap size between elements, decreasing the amount of overlap between elements, and decreasing the flap deflection angles were all means of decreasing the size of the multielement airfoil wake. Perry’s study can be used to help predict which multielement airfoil configurations perform best and when wake bursts will occur.

In addition to gaining satisfaction from the success of undergrads he helps, Pomeroy has engaged in activities to benefit his fellow graduate students.

He developed and implemented the annual Graduate Student Appreciation Week, during which seminars and social outings focused on AE graduate students are organized. He helped develop the graduate-student-led program aimed at inviting industry speakers to campus for departmental seminars, and has served as host for many of these speakers. Pomeroy is the key GSAC representative who addresses incoming graduate students at the Department’s fall orientation, and regularly provides tours for prospective graduate students.

Said Geubelle, “Over my 20-year academic career, I have never had the chance to work with a PhD student that has demonstrated such an enthusiasm and energy in improving the on-campus experience of our students.

“Brent is the perfect illustration of the great impact that a graduate student can have on the undergraduate and graduate programs of his/her Department.”