Lisha Yuan, engineering mechanics doctoral student in biomedical engineering and mechanics at Virginia Tech, received the Liviu Librescu Memorial Fellowship. The department selects a student each year for their impressive achievements and service in leadership, scholarly excellence, teaching, community service, and research.

“I didn’t expect to have so many opportunities as I have had at Virginia Tech," Yuan said. “I came here because it was one of the top programs for engineering mechanics. I’m glad that I have developed into the researcher I was meant to be.”

Yuan grew up near the Yellow Sea in China, in Nantong, a city near Shanghai. She began Virginia Tech’s engineering mechanics doctoral program in 2016, after receiving her bachelor’s degree in engineering mechanics from Hunan University. Her research focuses on finite element analysis, optimization techniques, and analysis of materials and structures.

Yuan is advised by Romesh Batra, a University Distinguished Professor and a Clifton C. Garvin professor in biomedical engineering and mechanics.

“Lisha Yuan is a very conscious and dedicated doctoral student who is a role model for other students in my team,” Batra said. “She is motivated to learn new and challenging material, to explore unchartered territories, and to successfully meet project objectives. I am fortunate to mentor her.”

In the lab, Batra's research group focuses on computational mechanics in studying phenomena governed by the principles of mechanics. The lab work is less hands-on with materials and more analytically and numerically driven, Yuan said. This enables them to analyze the physical response of structures with complex geometries, innovative materials, and structures that are subject to complicated loads.

“I am very grateful that I have such a great and outstanding advisor,” Yuan said. “He is one of the most professional people in the field of engineering mechanics. During my undergraduate study, I only had a few experiences in research. I’ve accumulated so many valuable ones here and my advisor’s passion for research and meticulous working attitude will always inspire me to continuously improve myself.”

Together, the group has been analyzing deformations of sandwich structures exposed to extreme loads. A sandwich structure, a type of composite material made of stiff face sheets and a softer core material, could be compared to a chocolate ice cream bar, said Batra. The “chocolate layer" represents the strong face sheets. In analyzing these structures, the group finds the ideal composition and thickness of the chocolate layer so the ice cream bar will not shatter when dropped on the floor, for example.

In optimizing sandwich structures, Yuan has enforced sandwich face sheets with carbon fiber and found the fiber orientation and thickness that is ideal and suitable for resisting extreme loads. She achieved this, finding the optimum sandwich designs for a better load-carrying ability, during her first few years in the engineering mechanics program.

“I knew I wanted to focus on the theory of engineering mechanics, which isn’t very common,” Yuan said. “I’ve learned so much here and am excited to apply my knowledge. In entering the program, my goal was to develop a new type of structure material. This has great applications to industry, such as automobile or aircraft, which are my interests.”

This past year, Yuan was given an opportunity to work with Bridgestone, to develop a new theory for a reinforced structure. She has focused on implementing this theory in commercial Finite Element Method (FEM) software to analyze the performance of reinforcements in the tire structure, with the end goal of designing a more reliable tire product. She credits the project with teaching her many new theories and skills.

Upon graduation, Yuan will join the tire mechanics team at Bridgestone. She hopes to develop innovative technologies to employ and use to serve society with superior quality products in the future. She is graduating earlier than expected, in March 2021 rather than May, due to the Virginia Tech Graduate School’s start-of-semester defense exception, where students may apply to graduate early — if all coursework is complete — once they complete a successful defense of their dissertation.

The fellowship, which supports academic and research excellence, is named in honor of the engineering science and mechanics professor who was among the 32 lives lost on April 16, 2007. 

Written by Laura McWhinney