Hans Wolfgang Liepmann (July 3, 1914 – June 24, 2009) was an American engineer and emeritus Theodore von Kármán Professor of Aeronautics at the California Institute of Technology.
He is known for his numerous contributions in fluid mechanics covering a wide range of problem areas, such as flow instability and turbulence, gas kinetics, viscous compressible fluids and liquid helium flows.
Hans Liepmann received a Dr.Ing.h.c. from the University of Aachen and a Ph.D. from the University of Zurich in 1938.
He started working at Caltech in 1939 as a Research Fellow in Aeronautics. He became Assistant Professor of Aeronautics in 1945, Associate Professor in 1946 and Professor from 1949 to 1974. From 1974 to 1976 he was Professor of Aeronautics and Applied Physics, from 1976 to 1983 Charles Lee Powell Professor of Fluid Mechanics and Thermodynamics and 1984-85 von Kármán Professor of Aeronautics. Since 1985 he was von Kármán Professor Emeritus at Caltech. At Caltech Liepmann was also Director, Graduate Aeronautical Laboratories from 1972 to 1985 and Executive Officer for Aeronautics from 1976 to 1985.
Liepmann received several awards, a selection:
- National Medal of Technology, 1993, for "Outstanding research contributions to the field of fluid mechanics"
- Otto Laporte Award, 1985, by the American Physical Society
- National Medal of Science, 1986
- Daniel Guggenheim Medal, 1986
- Fluid Dynamics Prize by the American Physical Society, 1980
- Ludwig-Prandtl-Ring, 1968 - from Deutsche Gesellschaft für Luft- und Raumfahrt
- H. W. Liepmann and A. Roshko, Elements of Gas Dynamics, John Wiley & Sons Inc. (1957), Dover Publications (2002)
- H. W. Liepmann and A. E. Puckett. Introduction to Aerodynamics of a Compressible Fluid, John Wiley & Sons Inc. (1947)