Nothing is too big or too small for Assistant Professor Krishnan Suresh's research interest. What gets his attention is engineering complexity.
Suresh, who joined the department's faculty in January 2003, is primarily interested in researching physical simulations of complex mechanical systems that span a wide range of geometric scale. A typical example would be an aircraft engine, where the largest component might be 100 times the size of the smallest component.
Each of the components is critical to the operation of the engine, according to Suresh, but computer-based analysis of complex systems is often difficult. In the case of an airplane engine, researchers would typically try to simulate the impact of vibration, stress, and wear on its performance. "The astuteness with which such complex models are simplified, at the outset of an investigation, is the very crux of engineering analysis," he said.
Suresh's goal is to develop new mathematical and computational tools for the rigorous simplification and simulation of such complex systems. For starters, he has received a $287,530 grant from the National Science Foundation to study methods of better analyzing thin mechanical components.
Thin components are used extensively, for example, as the outer shell of automobiles and airplanes. Such components undergo a rigorous computational analysis before they are put into production. Existing mid-surface computational methods of analyzing thin components are restrictive and prone to inaccuracies. Suresh wants to replace the existing computational models with a skeletal approach that would provide a more robust and predictable method for analyzing thin components.
Suresh spent four years in the industry after receiving his PhD from Cornell University in 1998. He worked as a senior mechanical engineer/engineering manager at Kulicke and Soffa Industries in Philadelphia, designing complex mechanical systems for the semiconductor industry.
Suresh also enjoys running, swimming and listening to Indian classical music.
Assistant Professor Heidi-Lynn Ploeg knows of what she speaks when talking about her research into designing orthopedic implants.
Before joining the Department of Mechanical Engineering faculty this fall, she spent 10 years in Switzerland as a project manager in the research and analysis department of a major orthopedic manufacturer.
Ploeg's work at Switzerland's Centerpulse Orthopedics provided her with a strong background in the orthopedics industry. But the Canadian native wanted to focus on academic research and teaching, and moved to Wisconsin last year without knowing much about the ME department at UW-Madison or its work in the emerging field on orthopedic-related engineering.
"I started seeing more research that was in my field," she said. "I realized there was a lot going on here."
She was invited by the department to give a research presentation under the Lindbergh Lecture Series, and shortly afterward was hired. Her research focused on orthopedic implants. According to Ploeg, two major problems continue to plague orthopedic implants excessive wear and loosening at the bone-implant interface. Part of the loosening is attributed to the implants causing a change in the bone loading to which the bone adapts by changing its density.
"It can cause the implant to loosen and that's what we're trying to avoid," she said.
Ploeg is working on creating predictive tools that demonstrate how bone reacts to implants. In addition, she plans to research fluid flow within bones, and the impact of mechanical loads on bone growth.
Ploeg is affiliated with UW-CREATe, a College of Engineering research center that focuses on rehabilitation engineering and assistive technology and includes faculty and staff from the Departments of Mechanical Engineering, Biomedical Engineering, and Rehabilitation Medicine. She would also like to work with faculty in the School of Veterinary Medicine on damage accumulation in the bones of thoroughbred racehorses.
She has a BS, MS and PhD from Queens University in Ontario, Canada, and is also affiliated with UW-Madison's Department of Biomedical Engineering.
In her spare time, Ploeg is an avid bicycle rider, and hopes to take part in competitive road bicycle racing.
Assistant Professor Frank Pfefferkorn is a mechanical engineer, but he spends considerable time researching material behaviors.
Pfefferkorn, who joined the department's faculty this past summer, focuses on laser-assisted machining, nano-manufacturing, and radiation thermometry. As such, he spends considerable time investigating the way materials behave for instance, under high heat flux and strains associated with novel laser-assisted machining techniques.
"There is a close link to materials science," he said.
Born in Germany, Pfefferkorn grew up in Philadelphia. He received his PhD and MS degrees from Purdue University after getting his BS degree at the University of Illinois at Champaign-Urbana. He came to the Department of Mechanical Engineering after a six-month post-doctoral degree period of study at Purdue.
In his research, Pfefferkorn focuses on laser-assisted machining of structural ceramics, as well as laser-assisted friction stir welding. Friction stir welding is a solid-state joining process that combines forging and extruding, and does not involve creating a true welding process. That's because friction stir welding works at temperatures below the melting point of the material being worked on. It also creates less distortion of the material worked on.
In general, according to Pfefferkorn, the goal of the research is to improve manufacturing capabilities of components with unique properties, such as alloys used in shipbuilding or vehicle manufacturing. Pfefferkorn also hopes to work with NASA on machining and welding in space.
"With regards to structural ceramics, you're limited in how you can shape these rather expensive materials," he said. "This laser-assisted machining will hopefully be another tool. The motivation here is to speed up the manufacturing process and improve production rates without introducing flaws or damage in the part. If we can improve the manufacturing speed, we can make it more economically attractive."
In his spare time, Pfefferkorn enjoys sea kayaking, cross-country skiing, and photography.
ME News is published twice a year for alumni, students and friends of the ME department.
Send address changes and other correspondence to:
Department of Mechanical Engineering
For HTML and other technical matters, contact:
Date last modified: Tuesday, 17-Feb-2004 11:47:00 CST
Copyright 2006 The Board of Regents of the University of Wisconsin System
| ME News homepage | Department of Mechanical Engineering | College of Engineering | UW-Madison |