By James Dungeon
Landing was like riding a bucking bronco.
“We had no idea what we were looking for,” recalled Earl Duque, who was part of a team troubleshooting the problem for NASA’s Ames Research Center. “All we could do was look at the data.”
Duque, then an engineer about to get his doctorate from University of California, Davis, ran the the figures through imaging software. The computer visualizations, though rudimentary by today’s standards, gave color and shape to forces otherwise invisible.
While flipping through them, Duque noticed something odd: a large circle with no obvious source. He walked the simulation backward — it was coming from dual avionics boxes — then forward — it was hitting the helicopter’s tail.
“That circle was a vortex from the boxes kicking up and hitting the tail,” Duque said. “They covered up the boxes, flew it, and it worked.”
Nearly two decades later, after 13 years as a NASA engineer and six years as an associate professor at Northern Arizona University, Duque went to work for Intelligent Light, the same company that created software like the kind he used to solve the Apache helicopter problem.
Imaging and imagining
During the 1990s and 2000s scientific visualizations become widespread, if not standard.
Today, they minimize time and money for prototypes and accelerate troubleshooting, among other things.
“This software is used to look at everything from shampoo and toothpaste to supersonic jets and the space shuttle,” Duque said recently in his Prescott home.
All those processes have at least one thing in common — the interaction of gases and liquids with solid surfaces — as predicted by computers with Computational Fluid Dynamics, or CFD, and given substance with visualization software.
“It basically comes down to three equations,” said Duque, who, as Intelligent Light’s applied research manager, talks about these sort of things with engineers and laypeople alike. “We use computers to solve these equations and plug those results into our software.”
(You might remember the equations from high school physics: Conservation of Mass, Newton’s Second Law of Motion, and Conservation of Energy.)
The challenge isn’t the physics; it’s the sheer number of calculations.
Picture a room filled with Legos. Each brick contains three equations, which must remain balanced at all times. Every time you move a brick, you’ve got to balance its equation along with all of the other bricks’ — even those seemingly far from the action — as the movement of one has ramifications for all.
“Let’s say there’s 100,000,000 bricks in this room,” Duque said. “That’s three equations per brick, and 300,000,000 equations to solve.”
If you’re measuring the pressure on a plane’s wing, the circulation of air in a car, or a wind turbine’s wake, there are exponentially more equations.
To crunch those numbers, Duque accesses some of the world’s most powerful supercomputers, some of which have the equivalent computing power of 4,000 computers. For the past two years, he’s done that remotely from his office in downtown Prescott.
Industry, academia, and extracurriculars
Computer simulations, almost by definition, fall short of reality. Still, they offer broader, conceptual insights.
“Visualizations give you a better understanding of processes,” said Dr. Roger Strawn, U.S. Army Aeroflightdynamics Directorate. “You can measure forces, but unless you can see them, it’s hard to know what’s really going on.”
Furthermore, they’re invaluable when securing funding or convincing management of a project’s importance, Strawn said.
“People joke that CFD actually stands for Color For Directors — that’s an inside joke usually meant in a derogatory sense — but these visualizations help people understand what we’re doing,” he said. “They’re beautiful and compelling, and can certainly be viewed as art, there’s hardcore engineering behind them, as well.”
Because of their value to industry, they’ve saturated the field, which has ramifications for academia.
“When Boeing makes prototypes for airplanes, for instance, they do lots of computer simulations before they build a single prototype,” said Dr. Shigeo Hayashibara, associate professor of aerospace and mechanical engineering at Embry-Riddle Aeronautical University’s Prescott campus. “That’s why we have to focus on educating students on that technology.”
That’s also why Hayashibara jumped at the chance to use FieldView, one of Intelligent Light’s flagship programs in the classroom courtesy of Duque two years ago. In addition to the software-assisted insights, Hayashibara said there’ve been other advantages to consulting with Duque.
“It’s hard to find somebody like Earl who’s got experience in industry and academia and understands the demands of both,” Hayashibara said. “I think he’s a great role model for the students.”
It’s also hard to find a friend like Duque, he added, who’ll drop everything for shop talk and sushi or join students to discuss complex physics over drinks.
“And did he tell you about dancing?” Hayashibara asked.
Strawn, who worked with Duque at Ames Research Center in the early ’90s, elaborated on this.
“Earl was totally into the dance scene,” he said. “That’s not something you can picture every engineer doing.”
Strawn once wrangled a date with a woman at an upscale club, and, in a panic, tapped Duque.
“Someone who’ll give you an emergency salsa dance lesson?” Strawn said. “Now that’s my definition of a true friend.”
As an undergraduate at Northern Arizona University in the early 2000s, Abigail Arrington’s first exposure to Computational Fluid Dynamics and scientific visualizations was via Duque.
“Here were images, this simulation, based on the numerical quantities and theories he’d been teaching in class,” Arrington said. “That’s what really drew me in.”
After finishing her degree she continued studying with Duque as a graduate student working on wind energy.
“Earl taught me how to do CFD computations in a thorough, professional manner … and to always question my results and make sure they were right,” Arrington said. “These aren’t skills I learned in a classroom — I’m not sure you could teach those skills in a classroom — but he instilled these practices in me.”
Today, Arrington is an application engineer at Altair Engineering, a company that does similar work to Intelligent Light, and sometimes partners with them.
“I think everyone loves to look at images,” she said. “But there’s so much more to these visualizations; they tell a story.”
Just how compelling that story is, however, might depend on your interpreter.
“He’s always been focused on telling a story. That’s what visualizations are really about,” Arrington said. “That’s what made Earl such a great teacher and why he’s so good at his job.”
Despite an exponential growth in computer processing looming on the horizon, Duque believes there’ll always be a human element to scientific visualizations.
“More computing power means more solutions processed for simulations,” Duque said. “What we’re really doing is coming in with automation tools that allow engineers to digest information so they can understand it better.”
That’s a familiar scenario to Duque — one that harkens back to the Apache helicopter simulations he saw in the early ’90s.
“We solved the problem because of that circle, and it’s not something we were even looking for,” Duque said. “That’s the power of visualizations.”
Earl Duque has managed the Applied Research Group for Intelligent Light since 2006 and has lived in Prescott since 2011. He also teaches Argentine Tango with his fiancé Delisa Myles, a Prescott College dance and choreography professor. You can usually find them dancing at The Raven Café or the summer dances on the Yavapai County Courthouse square. Visit ILight.Com and Meetup.Com/Prescott-Tango for more info.
James Dungeon is a figment of his own imagination. And he likes cats. Contact him at JamesDungeonCats@Gmail.Com.
Tags: Ames Research Center, Apache helicopter, CFD, Computational Fluid Dynamics, computer simulations, Conservation of Energy, Conservation of Mass, Earl Duque, Embery-Riddle Aeronautical University, FieldView, Intelligent Light, NASA, Newton's Second Law of Motion, Northern Arizona University, Roger Strawn, scientific visualizations, Shigeo Hayashibara, U.S. Army Aeroflightdynamics Directorate, University of California Davis