Prof. Dr. Ir. Leen van Wijngaarden

Scientific staff - Emeritus - Multiphase flow, acoustics, gravity waves


Leen van Wijngaarden was born in Delft, The Netherlands on March 16, 1932. After attending the "Grotius Gymnasium" there, he studied at the Technical University of Delft, where he got an Engineering Degree in 1956 and a Ph.D. in 1962. In between he fulfilled 2 years of compulsory service in the Royal Dutch Air Force. The title of his thesis was "Applications of the One-Fluid and the Two-Fluid Model in Magnetohydrodynamics", under the supervision of the theoretical physicist Professor L.J.F. Broer. In the mean time he was married to Willy de Goede (passed away October 2012), with her he got two sons.

In 1962 he entered the service of the "Netherlands Ship Model Basin", now called MARIN, in Wageningen, situated in the middle of the country. He did research there on gravity waves, cavitation, and gas-liquid flows. In 1963 he became head there of the "Hydromechanics" Division.

In 1965 he was appointed part-time Professor of Fluid Mechanics at the newly founded University of Twente in Enschede, the Netherlands. In 1966 he moved to Enschede to become full time Professor there in Fluid Mechanics, in the Department of Mechanical Engineering and on from 1969 also in the, founded in 1969, Department of Applied Physics. In his laboratory he worked with students and promovendi on a variety of subjects: cavitation, two-phase flow, gravity waves, acoustics, non-Newtonian fluids. He supervised 25 Ph.D students. The work in his group drew attention both in the Netherlands and internationally.

This led to an invitation from the California Institute of Technology to spend a year there as "Fairchild Distinguished Scholar". This was realized in the academic year 1974–1975. In the 1970s fluid mechanics was not supported by FOM, the Dutch funding foundation for Physics. Together with Gerrit Vossers from Eindhoven and Charles Hoogendoorn from Delft, Leen was instrumental in organizing Dutch scientists working in fluid dynamics into a coherent body. This was sufficiently successful in the open programme (Beleidsruimte) of FOM to lead in 1987 to the establishing of a Division of Fluid Mechanics within FOM. Leen was the first Chairman of this Division. He was active also internationally, for many years in EUROMECH, the European organisation for Mechanics, and in IUTAM, the "International Union of Theoretical and Applied Mechanics". He served IUTAM in many capacities,a.o as President from 1992–1996. He is still a Member-at-Large of the General Assembly of IUTAM.

He was elected Member of the Royal Dutch Academy of Arts and Sciences (KNAW) in 1988. The Dutch Queen made him “Knight in the Order of the Dutch Lion“ (Ridder in de Orde van de Nederlandse Leeuw) in 1995. Leen retired officially in 1997, but still continues scientific activities in the group of his successor, Detlef Lohse, at the University of Twente.

Honours and Offices