Ronald G. Larson

Ronald G. Larson

University of Michigan

Chemical Engineer
Awarded Bingham Medal 2002
Fellow, Elected 2015

Ron Larson obtained all three of his degrees at the University of Minnesota, graduating with a B.S. in 1975, M.S. in 1977, and completing a Ph.D. with L.E. ‘Skip’ Scriven in 1980. Upon graduation, he took a position at the famed AT&T Bell Laboratories, and, rose to become a Distinguished Member of the Technical Staff. After a remarkably productive period there, he left in 1996 to join the faculty of the University of Michigan as a Professor in the Chemical Engineering Department. He became the Granger Brown Professor and Chair of the Department of Chemical Engineering from 2000-2008. In 2014, Larson was named the A.H. White Distinguished University Professor of Chemical Engineering.

Ron has made significant contributions to many major areas of rheology, including constitutive modeling, the flow of liquid crystalline polymers and single molecule dynamics. His research at Bell Labs in the 1980s helped make critical connections between molecular and continuum approaches to constitutive modeling that were not previously appreciated. This culminated in his book, Equations for Polymer Melts and Solutions (Butterworths, 1988). His work with D.W. Mead and Doi (2001 Bingham Medalist) on constraint release theories helped show how to apply the Doi-Edwards theory for entangled networks to polydisperse systems and highly nonlinear flows. Likewise, his work with McLeish (2010 Bingham Medalist) provided critical insight into the competing roles of chain alignment, arm retraction and backbone stretching for classes of branched polymers. Their 1998 "pom-pom" paper won the Journal of Rheology Publication Award and remains one of the most-cited papers in the Journal of Rheology. Driven by the stimulating surroundings of Bell Laboratories in the 1980s and early 90s, Larsen also focused on understanding the evolution of microstructure in Liquid Crystal Polymers (LCPs) due to flow. In particular, his studies of arrested tumbling during shear (1990) and the importance of "textured domains" (1991) with Doi form the basis for much of the present state of knowledge of the dependence of LCP structure on imposed flow fields. Larson’s collaborations with Nobel Prize winner S. Chu and others on observations of DNA molecules in shearing fields has helped reveal the unraveling dynamics in shear and extensional flow that give rise to macroscopic non-Newtonian effects in the stress of the system. During his time at Bell Labs, Larson (together with S.J. Muller and E.S.G. Shaqfeh) also discovered a new class of ‘purely elastic’ flow instabilities in Taylor-Couette flow. In addition to his book on constitutive models, he has authored The Structure and Rheology of Complex Fluids (Oxford, 1999) and Rheology of Molten Polymers: From Structure to Flow Behavior and Back Again with John Dealy (Hanser Gardner 2006).

He is a fellow of the American Physical Society (1994) as well as a member of the National Academy of Engineering (2003), and he served as Prudential Distinguished Visiting Fellow at Cambridge University, England in 1996. Larson was awarded the Bingham Medal in 2002. He has served The Society of Rheology in numerous roles, including as President from 1998-1999.