Cutting Down the Commute

Each day at five o'clock, the highways of Northern Virginia fill with hundreds of thousands of cars and trucks. Under the best of circumstances, these vehicles add thousands of tons of carbon dioxide and other pollutants to the atmosphere every evening. When there is a bottleneck, the amount of carbon dioxide and other harmful substances injected into the atmosphere skyrockets.

Companies like Atlanta-based AirSage have developed a technology that uses cell phone traffic to spot congestion in real time. It collects the positioning information that all active cell phones generate to determine how long it takes drivers with cell phones to traverse a specific section of road. With this information, transportation agencies could urge motorists to take alternative routes.

The Virginia Department of Transportation is considering adopting the AirSage system. Its research arm, the Virginia Transportation Research Council, has asked Associate Civil and Environmental Engineering Professor Brian Smith, an expert on intelligent transportation networks, to validate AirSage's information. Undergraduate Christopher Foley (CE '09) is assisting Smith.

Foley's first job was to take a GPS-equipped car and join commuters along specified routes in Northern Virginia. He spent the better part of two weeks driving in rush-hour traffic. “Fortunately, the car we used came with XM Satellite Radio, so I had something interesting to listen to,” he says. Foley then compared the GPS data for each segment to the cell phone data AirSage generated for the same period. To do this, he had to cull any erroneous data from his database and use a statistical software package.

“It was a challenge,” Foley says. “I got support from Professor Smith and his graduate students, but I also liked having the responsibility for getting the work done correctly and on time.”

A Microturbine in the Basement

Associate Mechanical Engineering Professor Harsha Chelliah has a vision of an energy-efficient building whose electricity is generated by an individual microturbine. The turbine would be fueled by syngas, a mixture of hydrogen and carbon monoxide that could ultimately be produced from sewage or municipal waste. To make this system even more efficient, he would capture the waste heat from the turbine for heating and cooling purposes. With assistance from Andrew Voegele (Aero '08), he is taking the first steps toward reaching this goal, modifying a Capstone C30 microturbine to burn syngas.

“We are starting by using natural gas, a fuel that's typically used with microturbines, and making a series of measurements,” Voegele explains. “We will then use thermodynamic modeling software to predict the optimal mixture of hydrogen and carbon monoxide in syngas, which when combined with methane provides similar volumetric flow rates and heating values.” Voegele has also learned to use a computational fluid dynamics software package that will enable him to forecast the stability of the syngas combustion.

Voegele first encountered Chelliah in a thermodynamics class and got his start doing research by simply asking him if he had any projects available. “This is a great opportunity for me,” Voegele says. “I really like the modeling process, and I'd like to pursue working with modeling in the future.”

Keeping Airplanes Flying Longer

It takes a lot less energy to maintain an airplane than to build a new one. To keep that airplane flying, however, it must be corrosion free. When maintenance crew members detect corrosion on an airplane's aluminum skin, they coat it immediately with one of several corrosion-prevention compounds (CPCs). The catch is that no one really knows definitively how long this temporary fix lasts.

David Ojumu (Aero '08) is helping Materials Science and Engineering Professor Robert Kelly test the effectiveness of different CPCs on aerospace-grade aluminum samples collected from military bases around the country. He analyzes them in a number of ways and compares his data against a protocol for CPCs developed by former graduate student Feng Gui (MSE '06). He also determines if there is a relationship between the recurrence of a specific kind of corrosion and the sample's failure signature.

Ojumu has been working in Kelly's laboratory since the summer after his first year. “That first summer was a huge learning experience because chemistry is not my strong point,” Ojumu recalls. “I got a great deal of help from the people I worked with, and now I've spent more time in the laboratory than many graduate students.”

In fact, one of the perks of Ojumu's work is his access to Kelly. “Professor Kelly is highly regarded in the field,” he says. “It's mind-blowing to be able to sit down in his office and hear him talk about corrosion.”