Carolyn Fisher ’07 Uses Computational Modeling of Blood Flow to Study Aneurysms

Undergraduate mechanical engineering majors rarely have the opportunity to perform extensive research with the potential to impact medical treatments. This year, Marquis Scholar Carolyn Fisher ’07 (Mahopac, N.Y.) is practically applying her skills to help improve treatments for aneurysms.

Fisher is conducting honors thesis research on the computational modeling of blood flow in aneurysms. She is investigating the influence of different models for blood behavior on the calculated forces of blood vessel walls and risk of aneurysm rupture.

She also is modeling cerebrovascular aneurysms and considering the effect of a non-Newtonian model for blood behavior in these vessels. Non-Newtonian fluids have more complicated viscosities than fluids like air and water; for example, blood is a suspension of blood cells in plasma, and the cells tend to aggregate and clump in ways that make blood act differently in regions of fast or slow flow.

“The goal for my honors thesis is to determine how important non-Newtonian models for blood are when studying aneurysms through numerical simulation,” Fisher explains. “I am trying to determine which models fit which situations – geometry, blood velocity, etc. – most accurately. This project will hopefully be a step toward enabling researchers and doctors to gain a more accurate view of the hemodynamics of aneurysms – blood flow, pressures, wall shear stresses, etc. If there is a better understanding of exactly what is happening within an aneurysm, better medical decisions can be made concerning treatment.”

Fisher’s honors thesis is a continuation of EXCEL Scholars research she conducted this past summer with Jenn Rossmann, assistant professor of mechanical engineering. Rossmann is also Fisher’s thesis adviser. Fisher laid the foundation for her current work by conducting a thorough literature review and becoming familiar with computational fluid dynamics methods and software.

In Lafayette’s distinctive EXCEL Scholars program, students conduct research with faculty while earning a stipend. Many of the more than 160 students who participate each year share their work through articles in academic journals and/or conference presentations.

The EXCEL work made Fisher aware of the gravity of aneurysms and the importance of knowing more about them in the development of treatments.

“Performing the EXCEL research initiated my interest because it gave me a much better idea of the risks and dangers associated with aneurysms and why it is so important to study them,” she says. “There is still little knowledge about the causes of aneurysm growth and rupture, making their behavior very unpredictable. The research I am performing is a step, although very small, toward improving medical decisions and saving lives.”

Rossmann, who received a $139,590 grant this past summer from the National Science Foundation (NSF) to continue her research in the study of blood flow through vessels, has been impressed with Fisher’s motivation and aptitude for independent research.

“Carolyn has a strong record of academic excellence, an interest in current problems in biomedical engineering, and good time management skills,” she says. “These all helped me feel confident in her ability to contribute to this research. Learning how to manage a long-term project like this one and to resolve research challenges and persevere will certainly help her in graduate school and beyond. Research can test your patience; things rarely work the first time or even the 10th time, making research very different from class work.”

Fisher believes she found an ideal mentor in Rossmann, whom she got to know by taking the professor’s heat transfer course last year. Because blood flow through vessels is one of Rossmann’s primary research areas, Fisher feels comfortable approaching her when she encounters obstacles and setbacks within the research.

“Working with Professor Rossmann has been a wonderful experience,” she says. “She has always been there to help and guide me but has left me to solve most of the problems I encounter on my own. This has made my research project a very valuable learning experience. She is definitely highly qualified and is a caring mentor. From my meetings with her for both class and research, I have found her to be extremely intelligent and adept at problem solving. Also, because she has already been performing research similar to mine for the past few years, she is very understanding of my frustrations and problems.”

Rossmann’s primary research interests are the hemodynamics of diseased vessels and aerodynamics of sports balls. The NSF grant she received will be used to acquire a 3D Particle Image Velocimetry system for making measurements of fluid flows. Most of Rossmann’s work is computational, and the system will allow her to perform physical experiments on vessels similar to the ones she has modeled numerically on the computer.

Since joining the faculty in 2005, Rossmann has mentored six students in honors thesis and EXCEL research. She has published articles in academic journals such as Annals of Biomedical Engineering, International Journal of Engineering Education, and Journal of Biomechanics.

Rossmann is a member of the American Physical Society, American Society of Mechanical Engineers, American Society for Engineering Education, and Council on Undergraduate Research. She earned Ph.D. and B.S. degrees from the University of California-Berkeley.

“It’s exciting for me to be able to involve undergraduates in these projects, and to give them what they need to achieve success,” says Rossmann. “Lafayette is very special – few places give undergraduate mechanical engineers the chance to perform independent research. By completing an honors thesis, Carolyn will be making a meaningful contribution to an open problem in biomechanics. Many faculty members, like me, are energized and motivated by the students’ learning and successes.”

Fisher, who plans to pursue a Ph.D. in biomedical engineering, believes the field will allow her to combine her love for problem solving with her interest in biology and medical issues. She is confident that her Lafayette education will allow her to follow a number of different paths after graduation.

“The ‘small school effect’ of Lafayette has really enabled me to get to know some of the professors well and also form close relationships with some of the other mechanical engineers,” she says. “Mechanical engineering at Lafayette also seems to open a lot of doors for students after college. The other students who are pursuing jobs have been able to take their education in several directions, not just engineering. My major has not just taught me textbook material, but also how to think and solve problems.”

A member of the women’s varsity soccer team, Fisher was named to the 2005 Patriot League Women’s Soccer Academic Honor Roll. She was part of the student team that earned a $75,000 grant from the Environmental Protection Agency’s P3: People, Prosperity and the Planet Student Design Competition for Sustainability. She also participated in a three-week study abroad course in Italy on medieval and Renaissance art and literature.

Chosen from among Lafayette’s most promising applicants, Marquis Scholars like Fisher receive a special academic scholarship and distinctive educational experiences and benefits. This includes a three-week, Lafayette-funded course abroad or in the United States during January’s interim session between semesters or the summer break. Marquis Scholars also participate in mentoring programs with Lafayette faculty and cultural activities in major cities and on campus.

Honors theses are among several major programs that have made Lafayette a national leader in undergraduate research. The College sends one of the largest contingents to the National Conference on Undergraduate Research each year; 40 students were accepted to present their research at this year’s conference.