Paul A. Libby

Libby died in La Jolla, California, on November 2, 2021, at the age of 100.

Libby was elected a member of the National Academy of Engineering in 1999 for contributions as a researcher, author, and educator who advanced knowledge of fluid dynamics, turbulence, and combustion through theoretical analyses. He was a Guggenheim Fellow and a Guest Fellow of the British Royal Society.

He joined the faculty of Polytechnic Institute of Brooklyn and advanced to the rank of Professor. At that time, the famous aerodynamicist Antonio Ferri, a friend of Theodore von Kármán, joined the Polytechnic Institute of Brooklyn. Libby worked with Ferri as an assistant for ten years. In 1962, when Sol Penner was looking for faculty for the newly-founded School of Engineering at the University of California, San Diego, Libby was recommended to Penner by von Kármán. He joined UCSD in 1964 as one of the 10 founding faculty members. He served as department chair from 1973 to 1976. He also served as Acting Dean and Associate Dean of Graduate affairs.

Libby's research focused on a broad range of topics in fluid dynamics including boundary layers, turbulence, aerothermochemistry and combustion. The structure of shock waves was exactly solved by Morduchow and Libby in 1949, demonstrating that the entropy of the gas goes through a maximum upon crossing the shock wave. He, along with Keith Stewartson, were the first to identify the eigensolutions of boundary layer equations and to study the uniqueness of the boundary-layer solutions. Homann flow, axisymmetric stagnation point flows, were generalized by Libby. Paul Libby, along with Kenneth Bray, discovered an important phenomenon known as Counter-gradient diffusion in turbulent flames, in a series of papers in the '80s which are considered important contributions to our understanding of turbulent combustion.

Libby received his bachelor's degree in 1942 and obtained his PhD in 1948, both from Polytechnic Institute of Brooklyn. He served in the United States Navy during World War II in between his Bachelors and Doctorate degrees; he was a Junior Grade Lieutenant when discharged.

Paul Andrews Libby (September 4, 1921 – November 2, 2021) was a professor of mechanical and aerospace engineering at the University of California, San Diego, a specialist in the field of combustion and aerospace engineering.