With his doctoral dissertation ‘Taylor-Couette and Rayleigh-Bénard turbulence: the role of the boudaries’, University of Twente researcher Xiaojue Zhu has won the NWO Physics Thesis Award 2018.
To acknowledge excellence in scientific research by young researchers, NWO established the annual NWO Physics Thesis Award in 2010. This year’s winner, Xiaojue Zhu, wrote what was judged to be last year's best PhD thesis in physics and will be awarded EUR 10,000. He wrote his thesis under the supervision of Prof. Detlef Lohse and Prof. Roberto Verzicco of the University of Twente and he defended it on 16 February 2018. Zhu will receive his award on 22 January 2019 during the annual national physics conference Physics@Veldhoven.
Ultimate turbulent regime
What makes Zhu’s PhD thesis so outstanding is the breakthrough that it has provided in a classic problem in hydrodynamics: the asymptotic scaling law for turbulent flow. First predicted by Robert Kraichnan in 1962, this phenomenon makes upscaling possible to arbitrary Reynolds number, however it requires extremely strong turbulence: stronger than can be created in the laboratory or simulated by computer. Zhu managed to penetrate into this “ultimate” turbulent regime using flow between two co-axial rotating cylinders with wall roughness and to demonstrate that it had been reached. Together with his colleague Ruben Verschoof, he recently published about this in Nature Physics.
In fact, this breakthrough is the topic of just one of the chapters of Zhu’s thesis. Among the various other things his thesis offers is an explanation to a controversy in the literature, about whether or not Kraichnan’s regime applies to Rayleigh-Bénard flow. (The answer is yes, but only in the case of extremely high Rayleigh numbers over 1014.) All Zhu’s results are written clearly and concisely in chapters that had already been published separately as articles in prominent journals. Prof. Detlef Lohse, Zhu’s PhD supervisor, characterises the dissertation as a “brilliant masterpiece” that “has opened an innovative and productive line of research,” and the Committee has endorsed this appraisal.
About the NWO Physics Thesis Award
The NWO Physics Thesis Award is awarded to the best Physics' thesis of the year (1st April 2017 – 30th March 2018). It was established with the aim of drawing attention to high-quality physics research by young researchers. The winner receives a bronze statue and a sum of 10.000 euro, which he or she is free to use as they wish.