News. taming high-temperature. surfaces in propulsion systems. U.Va. Department of Mechanical & Aerospace Engineering

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1 U.Va. Department of Mechanical & Aerospace Engineering School of Engineering and Applied Science SPRING 2014 taming high-temperature surfaces in propulsion systems Scramjets may be experimental, but they re not science fiction. In May 2013, an unmanned aircraft developed for the U.S. Air Force the X-51A WaveRider flew at more than five times the speed of sound in a test off California. Just 111 years after the Wright brothers first flight at Kitty Hawk, we ve now entered the era of hypersonic speeds. The Wrights first flight was 12 seconds long. WaveRider s lasted a little more than three minutes. If sustained hypersonic flight is to become a reality, researchers must find ways to tame the tremendous heat exceeding the melting point of most metals that hypersonic flow generates. That s the challenge taken up by Professor Harsha Chelliah and his interdisciplinary team of researchers. A traditional liquid coolant system capable of controlling temperatures of this magnitude would be prohibitively heavy. With a $2.2 million grant from the U.S. Air Force Office of Scientific Research, the team is seeking to produce a viable cooling system that uses a scramjet s own fuel as a coolant. This approach has many well-known advantages in addition to eliminating the excess weight of a traditional system, Chelliah says. The high temperatures crack the fuel, a process that absorbs much more energy than heating water. In addition, cracking smaller fuel molecules leads to rapid combustion, a key requirement for hypersonic combustion. But cracking, or pyrolysis, has a significant downside. It produces coke, which soon clogs the scramjet s cooling channels. Chelliah has teamed with Department of Chemical Engineering Professors Bob Davis and Matt Neurock to explore and to synthesize a robust catalytic coating to maximize pyrolysis while minimizing coke formation. It would do this by refocusing energy on breaking the carbon-carbon bonds in the fuel, rather than the carbon-hydrogen bonds. He has also partnered with Department of Materials Science and Engineering Professor Hayden Wadley, a specialist in directed vapor deposition techniques, to develop methods to apply this catalytic coating to the cooling channels. Colleagues from North Carolina State University and the University of Maryland also are participating. I think we have assembled a world-class team with the right combination of expertise to attack this challenging problem, Chelliah says. We are very hopeful about the outcome. The coatings developed can have other applications for example, to prevent coking in fuel lines of gas-turbine engines. Developing Leaders of Innovation

2 MAE today Contents A 3-D Education Chris Goyne Dedicated to Experiential Learning Relationships: The Next Dimension in 3-D Printing Profiles in Mechanical and Aerospace Engineering Writer Charlie Feigenoff Editor Josie Pipkin Graphic Design Travis Searcy Mountain High Media Photography Dan Addison Tom Cogill Dwight Dart MAE is published by the University of Virginia School of Engineering and Applied Science Department of Mechanical and Aerospace Engineering. An online version of the magazine is available at Address corrections should be sent to the Department of Mechanical and Aerospace, P.O. Box , Charlottesville, VA or lcs3b@virginia.edu. This department is clearly on the move. We continue to assemble an exceptional faculty, including world leaders in such fields as microscale and nanoscale heat transfer, hypersonic combustion, and biomechanics, and we re both expanding and deepening our expertise. This year we added our second Rolls-Royce Commonwealth Professor, Xiaodong Chris Li. Chris believes one way to develop high-value-added products is by combining natural materials like cotton fabric with techniques of nanotechnology. A perfect example is the process he developed to create an armored cotton T-shirt, an innovation that earned him a spot on The New York Times Year in Ideas. Our good fortune continues. We are in the process of hiring additional faculty members for the coming year and we shall soon have good news to report. We also are fortunate in our students, who are more accomplished and highly motivated than ever. As you ll read, NASA selected a proposal from a team of students in Associate Professor Chris Goyne s Capstone course to send a sensor 23 miles into the stratosphere to measure cosmic rays. Theirs was one of only 10 proposals that NASA accepted from universities nationwide. Our graduate students are also flourishing. Several have secured fellowships to the Engineering School s Graduate Teaching Internship Program, which provides an opportunity for them to polish their skills as teachers and decide if a career in academia is something they would like to pursue. I am pleased to report that the evaluations from the students in their classes have been glowing. Another high point for the department this year is our growing collaboration with the Curry School of Education and area school districts, a partnership that is putting 3-D printers in the hands of local middle school and high school students. Stratasys, a leading producer of 3-D printers, has long recognized our leadership in using this technology for educational purposes. Through careful lesson plans and working with teachers, we hope to ensure that more young people graduate with a fundamental knowledge of science and math. Take all this together and you can see that this is an exciting time for the department. But we couldn t have done it without the assistance of our devoted friends and alumni. Your support is always appreciated. It helps us in so many ways to provide an educational experience that is equal to the talents of our students. We thank you! With best regards, Message from the chair Hossein Haj-Hariri Professor and Chair 2

3 Developing Leaders of Innovation These modern tools are ideal for providing students context so they grasp the power of science and math. When you can apply a mathematical principle to make something, it s no longer an abstraction. Hossein Haj-Hariri, Department Chair a 3-d education The lunchroom conversations at Buford Middle School in Charlottesville have changed. Principal Eric Johnson reports that physics now ranks with sports and music as a topic for discussion and Department Chair Hossein Haj-Hariri couldn t be more pleased. Buford houses the first facility of the U.S. Laboratory School for Advanced Manufacturing Technologies, which opened in October. It is modeled on the MAE department s own Rapid Prototyping Laboratory, complete with 3-D-electronics and design software. These modern tools are ideal for providing students context so they grasp the power of science and math, Haj-Hariri says. When you can apply a mathematical principle to make something, it s no longer an abstraction. Similar high-tech laboratories called Commonwealth Engineering Design Academies are scheduled to open in the next two years at Charlottesville High School, Albemarle High School and Albemarle County s Jack Jouett Middle School. A sister facility focusing on aerospace is being developed for Sutherland Middle School, also in the county. These academies will serve as laboratories for integrating engineering design into science teaching, while also serving as a valuable platform for preparing the next generation of science teachers to use these technologies. The project, a partnership of the two local school districts and faculty in the MAE department and the Curry School of Education, is rapidly gathering momentum. It has attracted funding from a Virginia Laboratory School Planning Grant, the National Science Foundation and the local school districts. It is also generating a host of new ideas. The Charlottesville City School Division submitted a proposal to the U.S. Department of Labor to support an advanced manufacturing internship program in conjunction with the opening of its design academy. Collaboration is the essence of the program. Faculty members from the department are working closely with Curry School counterparts led by Professor Glen Bull, co-director of the Center for Technology and Teacher Education. They are partnering with local teachers to develop lesson plans, and the U.Va. group is providing real-time support for instruction thanks to a new videoconferencing system linking the schools. One idea that came out of these collaborations is to use 3-D printing to replicate technological artifacts from the history of science and engineering. Undergraduates used Alfred Vail s original patent document to create a working version of his telegraph. As a result of these innovations, outside interest in the program is growing. A television crew from Japan filmed a feature at Buford, and a representative from China s National Center for Educational Technology will spend a year in Charlottesville tracking the project. 3

4 MAE today Chris Goyne Dedicated to Experiential Learning Chris Goyne just made a small but significant change to his résumé. After serving the department as a research associate professor and director of the Aerospace Research Laboratory for more than 10 years, he accepted a post in August 2013 as a tenure-track associate professor. It s a change that makes a real difference, he says. I found that I really enjoy working with students, and as a tenure-track faculty member I ll have more opportunity to do so while continuing to focus on my research. He specializes in hypersonic air breathing propulsion, supersonic aerodynamics, hypersonic ground and flight-test techniques, and diagnostic and measurement technique development. As principal investigator for the Hy-V program, Goyne has already demonstrated a talent for encouraging students to outdo themselves. With his guidance, a team of student researchers developed a prototype scramjet for launch at the NASA-Wallops Flight Facility on the Eastern Shore of Virginia. More recently, students in his Capstone course on spacecraft design were one of 10 student teams nationwide selected by NASA to fly an experiment on a suborbital flight vehicle. The team proposed using a high-altitude balloon to send a sensor 23 miles into the stratosphere to measure cosmic rays, a source of considerable radiation exposure for flight crews on aircraft. To do so, they are developing a small satellite they dubbed the JefferSat cubesat to carry the payload. The students are using an onboard smartphone to record radiation levels and transmit this information to the ground. The satellite data will be used to validate NASA computer models of radiation risk. The balloon is scheduled to lift off from New Mexico in September. Goyne credits the quality of the students for the success of the project. This has been a multiyear project, he says; but that has not been a challenge for the students. They self-organize and continue the mission from one semester to the next, conceptualizing, planning, designing, building and testing the equipment. Thanks to their thoroughness and determination, I think NASA will find the results extremely valuable. 4

5 Developing Leaders of Innovation RELATIONSHIPS: THE NEXT DIMENSION IN 3-D PRINTING Ask Dwight Dart, and he ll tell you that the 3-D printer is the next disruptive technology capable of turning traditional manufacturing on its head. 3-D printers will jumpstart innovation by enabling inventors to go from design to prototype in days. At the same time, it will change consumers relationships with suppliers, giving average homeowners the freedom to produce their own replacement parts, for instance, whenever they need them. But as Dart points out, If you want students to grasp the transformative power of this technology, there s no substitute for hands-on experience. That s why the relationship he s forged with Stratasys, a leading manufacturer of 3-D printers, is so important. Dart is the design lab engineer in the department s $2 million Rapid Prototyping Lab, and he works tirelessly to spread the word about the School s educational uses of this technology. Three years ago, he delivered a talk at a Stratasys conference that highlighted the educational potential of Stratasys 3-D printers including such class projects as Lecturer David Sheffler s replica jet engine and Associate Professor Gavin Garner s 2-D printer. Stratasys was impressed. We thought that U.Va. did an excellent job of demonstrating what our technology can do in an educational setting, says Jesse Roitenberg, education channel manager at Stratasys. Dart s presentation eventually helped the groups find common ground. U.Va. has produced copies of the Hoo Print 2-D printer and the jet engine that Stratasys can take to trade shows and conferences, while Stratasys has contributed 3-D printing materials for Dart to use with students. The additional material from Stratasys gives us the ability to be a bit more adventurous and ambitious in our programs, Dart says. It s made it easier to implement our new advanced manufacturing curriculum and to integrate 3-D printing into our senior design sequence. The latest addition to the lab also comes from Stratasys: an Objet Connex 500. This advanced 3-D printer is capable of producing models or parts 20 x 16 x 8 and can use up to 14 different materials at a time for a high degree of realism. The parts that our students will be able to design for this machine will be jaw-dropping, Dart says. 5

6 profiles in mechanical & aerospace Engineering faculty houston wood Professor Houston Wood s career is a testament to the essential role that scientists and engineers can play not only in preserving a free and open society, but also in protecting the world from a nuclear holocaust. Wood is a globally acknowledged expert in the use of the gas centrifuge to enrich uranium. He established a Department of Centrifuge Physics at Oak Ridge National Laboratory and later worked on the U.S. Department of Energy s gas centrifuge development program. For more than two decades, he has helped governments determine if nuclear programs in other parts of the world are being dedicated to peaceful or military purposes. I see my role as establishing a technical basis for informed decisionmaking and productive negotiation, he says. Wood works frequently with nongovernmental organizations (NGOs) like the Institute for Science and International Security (ISIS). NGOs play a vital role in a democracy by generating useful information and providing independent evaluation of government actions, he explains. ISIS is widely recognized both as a source of authoritative information on nuclear programs in states that seek or possess nuclear weapons and as an important contributor to efforts to stop the spread of nuclear weapons. Alumni sonya smith There are several reasons why Sonya Smith ( 91) values her experience as a graduate student in the department. She enjoyed the camaraderie of her fellow graduate students, as well as their diversity. Even though we were all busy with our own projects, there was a real sense of community there, she recalls. Smith also appreciates the department s commitment to intellectual curiosity and the pursuit of knowledge. She is grateful to Professors Hossein Haj-Hariri and Houston Wood for guiding her through research on the hydrodynamic instability of swept-wing aircraft. Moreover, she was impressed that they also encouraged her to explore new fields. If I wanted to learn something new, there was always someone willing to help, she says. I ve talked to students from other programs, and they don t say those types of things. One of the most valuable lessons she took away was the importance of communicating clearly. I learned at U.Va. how to explain my research to other people in a way that s not overly technical. As chair of the Department of Mechanical Engineering at Howard University, Smith depends on that skill when working with colleagues from other disciplines. 6

7 Developing Leaders of Innovation undergraduate student Alexandra VanDine Not only is Alexandra VanDine ( 14) good at math, she also really enjoys it. When she arrived at U.Va., she was a year ahead in the mathematics curriculum and quickly took all the courses she needed for her applied mathematics minor. She was looking for her next computational challenge when she met Ryan Johnson, a graduate student with Professor Harsha Chelliah s combustion research group, and found a problem that would help her take her mathematical talent to the next level. Johnson models hypersonic combustion under conditions in which the flow of fuel and oxygen exceeds the speed of combustion itself. Ryan s mentorship has been pivotal in my development, she says. He s helped me sharpen my skills in virtually every aspect of research, from the basic literature review to data analysis. VanDine is also the current president of the student chapter of the American Institute of Aeronautics and Astronautics, where she has been focusing on helping members build their networks and sort through their career options. VanDine herself has no doubts about her next move. Once I started doing research and realized how much I loved it, she says, I knew that graduate school was in my future. graduate student nam le A doctoral student in Professor Pamela Norris research group, Nam Le ( 17) is interested in energy transport on the microscale and nanoscale. He is using computational techniques, including molecular dynamics, to simulate heat transport at interfaces between solids. His research sheds light on the thermal resistance that occurs between layers in electronics, which could lead to devices that run cooler and faster. The opportunities he has had as a graduate student have helped Le mature as a researcher and educator. Pam involves us in the proposal-writing process, he says. That s an invaluable experience. And she is really great in helping us connect with the larger research community. Le also earned a fellowship to participate in the Engineering School s Graduate Teaching Internship Program. The program gives students considering an academic career the opportunity to develop and co-teach a course with experienced faculty mentors. Le worked with Professor Harsha Chelliah. It was a huge amount of work, he said, but it was very satisfying. As the semester progressed, I started to feel more comfortable and self-assured in the classroom. 7

8 Non-Profit Organization US Postage PAID Charlottesville, VA Permit No. 164 University of Virginia Department of Mechanical & Aerospace Engineering School of Engineering and Applied Science P.O. Box Charlottesville, VA U. Va. Department School of E ngineering & Applied Science of Mechanical & Aerospace Engineering your gifts matter support your department Make a gift online to the MAE department on our secure website: giving.virginia.edu/engineering. Please designate Mechanical and Aerospace Engineering in the Special Instructions box on the form. If you have questions about giving to MAE, please contact Zak Richards at zak.richards@virginia.edu or Send your news, milestones and address changes to lcs3b@virginia.edu or P.O. Box , Charlottesville, VA join the conversation...