Detlef Lohse awarded APS 2017 Fluid Dynamics Prize
In celebration of JFM Editorial Board member Detlef Lohse recently being awarded the APS 2017 Fluid Dynamics Prize, I present a special blog entry on his work.
The Fluid Dynamics Prize citation honours Lohse for profound and wide-ranging contributions to our understanding of fluid turbulence, multiphase flow, and granular flows; for outstanding contributions to the teaching and training of future fluid dynamicists; and for long-standing service to the international fluid dynamics community.
Lohse’s work is summed up perfectly by the man himself: “It’s a combination of theory, experiments and numerics, it’s pretty visual and we are driven by trying to understand problems and phenomena.” When discussing his approach to research Lohse speaks of three main environments, each providing a different experience, that combined together to allow him to build his successful career. The first, his time in Germany as a student at the universities of Bonn and Marburg, where he “gained a good grounding in theoretical and statistical physics”; the second, the time he spent as a post-doctoral student at the James Franck Institute and the Department of Physics at the University of Chicago, which he describes as an “outstanding intellectual environment” where he “learned to develop a good taste for problems” and the third, his time at the University of Twente where he discovered a passion for engineering.
He stresses the importance of a problem-driven focus to his research and also mentions industry as a “source for inspiration where beautiful problems can be found.” His work on inkjet printing for example has its roots in problems encountered in industry. As Lohse puts it himself “there are many fundamental problems in industry where the core is really in fluid dynamics.”
Lohse’s PhD thesis investigated turbulence using statistical physics and in Chicago he began working on bubbles by attacking the problem of single bubble sonoluminescence – the emission of short bursts of light from a single bubble in a liquid when excited by sound. He also made one of many divergences into the field of granular matter. Since his appointment as a Professor at the University of Twente in 1998, Lohse has continued working in a wide variety of subject areas, including heat convection, turbulence, multiphase flow, and micro- and nano-fluidics. Lohses is keen to emphasise that fluid dynamics is a multi-disciplinary subject and there is a strong sense of this across his work.
Another central theme that can be seen in his research is the importance of technology as an invaluable tool for assisting fluid dynamicists with their investigations. Lohse explains how he used his initial start-up funding for his position at Twente (around €100,000) to invest in digital high-speed imaging, which at the time was a new and upcoming technology. This investment has continued throughout his time at Twente as he explains “We always renewed things with the latest high-speed cameras to ensure we would be at the forefront of digital high-speed imaging. We have been lucky because the last 20 years have been the golden time for fluid dynamics with the development of digital high speed cameras.”
The last sentence provides perhaps the greatest insight into Lohse as a person: humble, modest and a team player. When discussing his work everything is described as ‘we’ rather than ‘I’ and he mentions so many collaborators that I could not possibly include them without unfairly being selective.
In the future, Lohse wants to continue to bridge the gap between fluid dynamics and chemical engineering, beginning with his latest research grant which will see him work on diffusive droplet dynamics in multi-component liquid systems. He also wishes to continue to develop his theory on Rayleigh-Bernard convection and the existence of the ‘ultimate regime’ at sufficiently large Rayleigh number, as well as problems in two-phase flow, bubbles and turbulence. The overriding theme once again being a multi-disciplinary problem with foundations in nature and technology. “I think what’s important for the fluid dynamics community is to have open ears and eyes towards applications because that is where you can find inspiring problems that you simply wouldn’t normally bump into. Of course, purely curiosity driven research is also absolutely crucial and great fun to do.”