Julio M. Ottino is an engineering scientist recognized for his work in fluid dynamics, chaos and nonlinear dynamics, complex systems, and especially mixing. He was born in La Plata, Argentina and grew up with twin interests in the physical sciences and visual arts. He obtained his first degree at the University of La Plata, in Argentina, before receiving a PhD in chemical engineering from the University of Minnesota. His is currently at the McCormick School of Engineering and Applied Science in Northwestern University. Previously he held positions at the University of Massachusetts Amherst as well as chaired and senior appointments at the California Institute of Technology and Stanford University. He is the co-founder and director of the Northwestern Institute on Complex Systems (NICO) and the author of the Kinematics of Mixing: Stretching, Chaos, and Transport and The Nexus, Augmented Thinking for a Complex World, jointly with Bruce Mau. He is a member of both the National Academy of Sciences and the National Academy of Engineering.

Research Interests

Julio Ottino's group focuses on mixing of fluids and, primarily, granular mixing/segregation. His work involves theory, computations, and experiments. His initial work in fluids established the scientific basis of mixing, developing mathematical frameworks that, when coupled with experiments, showed that flows can produce a special kind of stretching and folding, related to the mathematics of horseshoe maps, that results in chaotic motion and effective mixing. These ideas have impacted multiple domains. He has been interested in extensions of this foundation to include chemical reactions and processes such as aggregation and fragmentation and applications ranging from microfluidics and materials processing to CO2 capture and geophysical sciences. His most recent work in mixing and segregation of granular matter exploiting the mathematics of piecewise isometries is connecting his work with new areas in mathematics, which has sparked an interest in the impact of pure math in physical sciences.

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Primary Section

Section 31: Engineering Sciences