Cengiz Camci, Ph.D.
Professor of Aerospace Engineering
233 Hammond Building
Penn State University
University Park, PA 16802
Phone: 814-865-9871 / Fax: 814-865-7092
E-mail: C-Camci@psu.edu
Web site: http://www.personal.psu.edu/cxc11/
In his office in the Hammond Building on Penn State’s University Park campus, Professor Cengiz Camci keeps a warped and corroded airplane part – a nozzle guide vane from a GE CF6 turbofan, which formerly powered a DC-10. The damaged component represents a turning point in Camci’s career. He was a master’s degree candidate in mechanical engineering at Bosphorus University in the late 1970s when the use of computers was still new. A professor taught him the finite element method of solving partial differential equations over changing domains. Camci needed an engineering problem on which to try it out, and modeling the heat transfer and cooling in turbine blades was perfect.
Thirty years later, Camci is still studying nozzle guide vanes, in particular improving their efficiency within turbines used for generating electricity.
Gas turbines are really good at generating electricity. A modern combined cycle gas turbine power plant can produce 500 megawatts of power, half as much as a nuclear power plant. They are easy to install and easy to operate as well as being both reliable and durable – typically running for 80,000 hours (about nine years) without a major shutdown. Another plus is that the natural gas for fuel is abundant in the United States and available through a broad network of pipelines.
Gas turbines have been providing electricity in the United States since the 1970s. The technology is mature, but optimizing their operation continues to present interesting engineering challenges. One of these is the loss of flow energy that takes place between the tip of the nozzle guide vane – the blade that makes the turbine spin -- and the interior wall of the nozzle. Another is that the hotter the turbine runs, the more efficient it is, but heat damages metal components. As a result, cooling systems have to be implemented – adding another layer of inefficiency and complexity to the system.
Turbines have become a lot more efficient in the last half century. In the 1950s, they typically operated at only about 45 percent efficiency. Today, it’s common for them to achieve 90 percent or better efficiency. Thus the improvements Camci hopes to achieve are incremental. At the same time, because so much electricity is involved, the improvements have the potential to save significant energy and to reduce undesirable emissions.
In 1996, with the cooperation of the NASA Glenn Research Center and the U.S.Army Research Office, Penn State installed a 3-foot diameter large-scale axial flow turbine, one of only a few in the United States. Located in a lab in the Hammond basement, the turbine is operated by a set of suction blowers. Whereas an actual gas turbine generating electricity would operate at about 2600F, the simulator operates cold. Still, as Camci explains it, the scale is accurate and the geometries are realistic, enabling researchers to study the viscous flow around the tips of the turbine blades so that ultimately the components can be designed to reduce aerodynamic loss, thus improving efficiency.
Another potential improvement in turbine design could be the use of ceramic rather than metal components because ceramics withstand heat better. But with poor tensile strength and a tendency to chip, ceramics fare poorly in a dynamic environment. One possible solution would be to use ceramics reinforced with metallic elements, but anything this radical would require industry to retool not only its manufacturing processes but also its thinking.
As Camci puts it, researchers are “the risk-takers, but we know going in that only a few of our ideas will succeed. This is partly because implementing new ideas is painful. As researchers, we might put something in a journal and nobody in a position to use it will look at it for 10 years. We are used to this.”
Besides turbines, Camci is overseeing research on several other projects including the damage sand causes to helicopter rotors. The combination of international politics and U.S. defense policy dictates that military helicopters frequently fly in sandy, desert conditions. Two of Camci’s students recently modeled the behavior of grains of sand around helicopter rotors. One thing they learned, Camci says, is that “sand doesn’t go with the flow.” At the same time, they determined that only a particular segment of the rotor’s leading edge is likely to be damaged by it. This information will enable manufacturers to retrofit helicopter blades with protective coatings only where the coatings do the most good. It may also influence the way future rotor blades are designed.
A native of Turkey, Camci grew up in Istanbul and in the northwestern coastal city of Bursa, where his father, a forest engineer, was sent by the government to establish the nation’s first national park. Mechanically minded kids in the U.S. take apart the lawnmower. Camci never saw a lawnmower till he came to the U.S. as an adult – so he took apart his mother’s sewing machine, and also his own toys. On a more constructive note, he designed and built kites, built a fully operational sailboat for two people during a single summer vacation, and along with his best friend rigged ropes and pulleys between their two apartment buildings so that they could send model airplanes and other things back and forth.
Camci earned his bachelor’s degree in mechanical engineering at Istanbul Technical University. After being awarded his master’s from Bosphorus University in 1980, he left Turkey for a one-year postgraduate program at the then NATO-sponsored Von Karman Institute for Fluid Dynamics in Belgium. At the end of the year, Camci was one of two in his class of 30 selected for a fellowship that eventually enabled him to stay on and earn his Ph.D. in Applied Science. In 1985, he was still there, working as a post-doctoral fellow, when a visiting aerospace engineering professor invited him to come to the United States and work with him at Penn State.
Camci joined the Penn State aerospace engineering faculty in 1986 and was appointed full professor in 2000. He numbers among his current projects several related to Penn State’s Turbomachinery Aero-Heat Transfer Laboratory, and he also is working closely with the International Gas Turbine Institute, IGTI. A fellow of the American Society of Mechanical Engineers, he is a frequent invited lecturer at the von Karman Institute’s lecture series program.
While Camci acknowledges that many universities emphasize research over teaching, he believes that “a university’s principal product is students” and maintains a web page devoted to his teaching philosophy and observations. Today he teaches graduate level classes in turbomachinery systems, the finite element method, and a new course he developed himself on propulsion systems for unmanned aerial vehicles.