Dr. Jivtesh Garg, AME Assistant Professor, and fellow research members recently developed a model that explains how heat flows between objects separated by gaps of less than a nanometer. The team has developed an atomistic framework that successfully predicts the magnitude of heat transfer across all gaps ranging from finite sizes all the way to perfect contact. The work overcomes the shortcomings of previous continuum based models which predict a diverging behavior at short length scales.
Through this model the team demonstrated that at gaps of few atomic layers, lattice vibrations (phonons) can tunnel through (normally associated with conduction heat transfer) in addition to heat transfer through evanescent electromagnetic modes (near-field radiation) blurring the separation between conduction and radiation at short length scales. By using microscopic Maxwell’s equations energy transfer was directly expressed in terms of short-range forces and long-range Coulomb forces between atoms on either side of a gap avoiding the need for use of any bulk macroscopic properties such as the dielectric constant. Such a purely atomistic framework of describing heat transfer can also benefit from ab-initio calculations that provide short-range interactions through solution of the underlying quantum-mechanical problem.
The work has implications for practical applications where heat transfer at small gaps is becoming increasingly relevant such as heat-assisted magnetic recording and nano-structured aerogel materials. By providing an accurate atomistic description the work also paves way for development of non-local dielectric constant which can be integrated into continuum models allowing an easier prediction of thermal transport at these small gaps.
The research team is made up of Vazrik Chiloyan, Massachusetts Institute of Technology; Keivan Esfarjani, Rutgers University; Gang Chen, Massachusetts Institute of Technology; and Jivtesh Garg. To view the paper regarding the team’s work, please click here. Additionally, the team’s work was recently featured in MIT News.
Dr. Singh visited from Oklahoma State University where he is the Associate Dean of Academic Affairs, Director of the Helmerich Research Center and C.F. Colcord Professor in the College of Engineering, Architecture and Technology.
Bio: Dr. Raman P. Singh is a C.F. Colcord Professor of Mechanical & Aerospace Engineering and currently serves as the Associate Dean for Academic Affairs for the College of Engineering, Architecture and Technology at Oklahoma State University. He is also the Director of the Helmerich Research Center at the OSU-Tulsa campus. He holds M.S. and Ph.D. degrees in Mechanical Engineering and Applied Mechanics from the University of Rhode Island and a B.Tech. degree from the Indian Institute of Technology from Kanpur, India. Prior to joining OSU in 2006, Singh was a faculty member at the State University of New York at Stony Brook. Before working in New York, he was a post-doctoral scholar at the California Institute of Technology.
Singh’s academic interests are in student mentorship, development and retention with a focus on new pedagogical methods. His research interests are in the mechanics of advanced materials with an emphasis on the investigation of modern engineered materials and development of new techniques for mechanical characterization at highly localized length scales. Besides academia, Raman enjoys road-trips, being a life-long student, photography and spending time with his two daughters.
Abstract: This seminar presented the use of quantitative atomic force microscopy based indentation to characterize the mechanical properties of a carbon fiber–epoxy matrix interphase at highly localized length scales. Atomic force microscopy is a valuable tool for qualitative characterizations of material surfaces. Nonetheless, its application to quantitative measurements is hampered by various technical issues. Accordingly, the talk will discuss how issues such as spring calibration, tip geometry, surface roughness and substrate effects were taken into account to obtain accurate quantitative mechanical proper ties of interphase region.
Lastly, the seminar discussed the use of surrogate modeling to characterize non-linear viscoelastic materials based on inverse analysis of indentation data. In this form, the technique can be extended to study mechanical properties complex biological structures such as the ear-drum (or tympanic membrane) or the heart wall.
Congratulations to Celeste Clary as she was named the Outstanding Underclassmen Student during the Society of Women Engineers (SWE) Week. Celeste is a sophomore studying mechanical engineering. She is from League City, Texas.
Congratulations from all of us at AME! Keep up the great work!
On Monday, April 6, 2015, the Space Systems and Mission Design class of the School of Aerospace and Mechanical Engineering hosted Mr. Keith Reiley, a Boeing Project Manager. Mr. Reiley spoke with students about current projects and advancements in the space industry, including some current projects at Boeing. Mr. Reiley is a University of Oklahoma graduate from 1982 with a degree in Engineering Physics.
Keith Reiley is currently the Boeing Commercial Crew Transportation System Program Manager. He has been managing the development efforts for Boeing’s Commercial Crew program since it’s inception in 2009. Prior to working at Boeing, Mr. Reiley was Director of the NASA ISS Mission Integration office, responsible for overall configuration and assembly planning, management of assembly missions and integration of international partners.
One of the remarkable legacies and contributions of AME is its significant interaction with industry. For over 100 years, our graduates have been a part of many well-respected companies. Our curricula and research activities have been helpful in building partnerships with industry. The collaboration of the internationally reputable Combustion and Flame Dynamics Lab at AME and John Zink Company is an example. The John Zink Company is an Oklahoma based a worldwide leader in burner manufacturing. In an effort to ensure that the next generation of energy and technology leaders will come from our graduates at the University of Oklahoma, a memorandum of understanding between the OU College of Engineering and John Zink Company was signed in 2007 through which funds are made available to support graduate students in the field of combustion. The memorandum was signed by Dr. S. R. Gollahalli, then Director of AME and head of the Combustion and Flame Dynamics Lab and Dr. Joseph Colannino, then Director of Research and Development of John Zink Company. The company founded in 1929 by John Steele Zink (an OU graduate), currently a division of the Koch group of companies, is a leader in the design and development of flares, process burners and boiler burners.
Since 2008, sixteen graduate students have been supported with the annual funding provided by John Zink Company. These students, designated as “John Zink Company Scholars,” are honored with individual awards from John Zink Company and certificates from AME. The students also take one of the several short courses on combustion that are offered at John Zink Company in Tulsa. In addition, their names are engraved in a plaque in Felgar Hall. John Zink Company is notified when the students are ready to graduate to provide the company with an opportunity to recruit them. The generous gift from John Zink Company has been helpful to the success of our AME graduate students in the field of combustion. Past John Zink Scholars are enjoying successful careers in industry (John Zink Company, Boeing, Schlumberger,) and academia (University of Texas-El Paso).
For the past several years, Dr. Charles E. Baukal Jr. has visited AME with some of his colleagues to present awards to the John Zink Scholars. Dr. Baukal is the director of the John Zink Institute and has been with John Zink Company since 1998. On March 27, 2015, Dr. Baukal presented awards to the John Zink Scholars for 2014-2015, Arun Balakrishnan, Ph.D. in Aerospace Engineering, and Mohammad Imran, M.S. in Mechanical Engineering.
AME Graduate Student Amber Kapoor was recently selected into the 2015 National Science Foundation (NSF) Graduate Research Fellowship Program. Amber will receive a stipend of $34,000 towards her research.
Amber is a Ph.D. Candidate in Mechanical Engineering. Her research interests include alternative energy and sustainability, specifically HVAC efficiency and controls. Following the completion of her Ph.D., Amber hopes to work in the energy industry contributing to sustainability research.
US News and World Report recently released their Best Graduate Schools in Engineering of 2015. Each school’s score reflects its average rating on a scale from 1 (marginal) to 5 (outstanding), based on a survey of academics at peer institutions. The School of Aerospace and Mechanical Engineering at the University of Oklahoma’s mechanical engineering graduate program was ranked 72nd improving greatly from 88th in 2014 and 93rd in 2013. In the Big 12 conference, both public and private, AME’s mechanical engineering graduate program was ranked third best following the University of Texas and Iowa State University. Click here to visit the list.
AME is grateful for their students, faculty and university leadership members for advancing the mechanical engineering graduate program while it continues to grow and succeed.
The School of Aerospace and Mechanical Engineering at the University of Oklahoma was selected in late February to participate in a program called Transforming Engineering Culture to Advance Inclusion and Diversity (TECAID). As part of the program’s initiative, TECAID selected five U.S. Mechanical Engineering departments from across the country who are working to improve diversity and inclusion related to race, gender and other social identities and that wished to benefit from an infusion of support and expertise.
“We, at AME, were thrilled to be selected for the TECAID program, because we have a vision of a fully inclusive mechanical engineering program and we see this as a great opportunity to help us reach that goal,” said Rebecca Norris, AME’s office manager and member of the TECAID team.
As part of the TECAID program, each department will define a diversity and inclusion change project and work together toward achieving their goals. Expected departmental outcomes include more diversity, less bias, greater inclusion and a more informed, responsible academic citizenry in matters of gender, race, sexual orientation and other social identities. Participation in this program means that the team from AME will attend three workshops over the next year and will also meet online.
“I am very excited about our participation in the TECAID program as one of the five mechanical engineering departments in the nation,” said Altan. “The program will give us a tremendous opportunity to transform engineering culture to advance inclusion and diversity. We have formed an outstanding AME team who will work with the national leaders to develop and implement effective strategies to enhance the recruitment, retention and success of underrepresented groups in mechanical engineering at OU.”
AME’s department team includes AME Director M. Cengiz Altan, Associate Professor J. David Baldwin, Associate Professor Wilson Merchan-Merchan, Professor Zahed Siddique and Rebecca Norris. This team will rely heavily on input from faculty members, especially female colleagues and those from underrepresented groups. AME believes the transformation of our school has to be driven from within, with the perception that the “majority” is driving the change.
“The TECAID program will help us discover more effective ways to recruit and retain underrepresented students in mechanical engineering to ensure that we are providing learning opportunities to top students from all groups,” said Siddique.
Please click here for more information.
Congratulations to Maryam Sabeghi, mechanical engineering graduate student, who was recognized by the National Science Foundation for Women’s History Month on her research. Maryam is a Graduate Research Fellow whose research focuses on solution space exploration in model-based realization of engineered systems. She believes her interest in engineering and how things work began when she was merely a child in Iran. To see the article featuring Maryam, please click here.
Jacob Anderson is an alumnus of the University of Oklahoma. In fact, Jacob is a three-time alumnus. He graduated from OU and the School of Aerospace and Mechanical Engineering with a Bachelor of Science in mechanical engineering in the spring of 2007, followed by his Masters of Science also in mechanical engineering in the summer of 2009. Lastly, Jacob graduated with his Doctor of Philosophy in mechanical engineering in the fall of 2013. Since then, he has worked with M. Cengiz Altan, AME Professor and Director, as a postdoctoral researcher.
Jacob recently accepted a job with PPG Industries working at the Fiber Glass Science and Technology Center. He will hold the title of Senior Researcher and Development Engineer in North Carolina. His job duties include identification, development and testing of textile composite materials for commercial development, work with customers to develop new applications, oversee production trials to evaluate material performance and more. Jacob believed working hard in both the classroom and the laboratory were key in landing his new job.
What do you enjoy most about your job/working in your field?
Composite materials are very exciting to work with because they allow materials to be developed that are optimized for a specific application or use. As such, the combinations/challenges are endless.
How did your education at AME help you to be successful in your career?
AME gave me the opportunity to pursue and overcome challenges both in and out of the classroom. As such, I have had many experiences and opportunities that have helped me grow as both a professional and a person. I feel very prepared for my career.
Why did you choose OU to pursue your degree?
The research being conducted by several members of the faculty aligned with my own interests.
What advice would you give to a current AME student?
I would tell the students:
- Your time at AME is what you make of it.
- Work hard, keep your eyes on your goal and keep pushing forward to achieve the goal, whether the distance traveled is measured in kilometers, meters or millimeters.
Who was your favorite faculty member and why?
Dr. M.C. Altan: He has the ability to present material from many different directions. As a result, he makes even the most complicated material approachable. In addition, his mentorship over the years has been invaluable and greatly appreciated.
AME would like to wish Jacob great success as he begins his new job!