Antony N. Beris

Antony N. Beris

University of Delaware

Chemical Engineer
Awarded Bingham Medal 2025
Fellow, Elected 2016
University of Delaware weblink
Citation

For the development of a new systematic approach to apply nonequilibrium thermodynamics to the modeling of complex fluid flow with applications to viscoelasticity and liquid crystals; for the stability analysis of viscoelastic flows and the first direct numerical simulations of polymer-induced drag reduction; for modeling thixotropy and blood rheology.

The Society of Rheology proudly announces Professor Antony N. Beris as the recipient of the 2025 Bingham Medal, honoring a career marked by exceptional theoretical and computational contributions to the field of complex fluid dynamics and rheology. The Arthur B. Metzner Professor at the University of Delaware, Antony has pioneered our modern understanding of how internal microstructure interacts with flow, across a wide spectrum of materials and applications. His higher education is a Diploma of Chemical Engineering from National Technical University of Athens and PhD in Chemical Engineering from MIT with Robert Armstrong (Bingham Medal 2006) and Robert Brown. He became a Fellow of the Society in 2016 and holds fellowships in APS (DFD, 2021) and AAAS (1999). Among other honors, he received the Willem Prins Award in 2015 from Delft University for his work in polymer rheology.

Professor Beris’s research spans microscopic to macroscopic modeling and simulation, uniting theory and computation to resolve important scientific and technical problems in our discipline. At the core of his work is the development and application of a rigorous nonequilibrium thermodynamics framework that integrates both reversible (Hamiltonian) and irreversible (dissipative) dynamics. His seminal monograph, Thermodynamics of Flowing Systems with Internal Microstructure (Oxford University Press, 1994, co-authored with B.J. Edwards), introduced a unified formalism using generalized Poisson and dissipation brackets. This approach laid a consistent theoretical foundation for modeling complex fluids such as polymeric systems, liquid crystals, emulsions, and thixotropic suspensions, and continues to be a defining reference in the field, with over 1400 citations.

Beris’s contributions to computational rheology are equally groundbreaking. In the 1990s, he and his collaborators pioneered direct numerical simulations (DNS) of viscoelastic turbulent flows using the FENE-P model, demonstrating polymer-induced drag reduction from first principles. These simulations tackled the formidable challenge of coupling three-dimensional unsteady Navier-Stokes equations with the evolution of a conformation tensor. The resulting insights helped elucidate the energy transfer mechanisms in polymer-laden turbulence and inspired a new generation of computational studies across the globe.

His early work on viscoplastic flows includes foundational contributions to the field. His 1985 J. Fluid Mech. paper, coauthored with Tsamopoulos, Armstrong, and Brown, provided the first detailed analysis of the creeping motion of a sphere through a Bingham plastic. The study introduced asymptotic approximations for drag and identified unyielded zones, setting a standard for future analyses of yield-stress fluids. Antony developed this further to make major contributions to the study of thixotropy and time-dependent rheological phenomena. His 2002 publication in JNNFM with Mujumdar and Metzner proposed a new structural model for thixotropic suspensions. Another hallmark of his work is the extension of the Cox-Merz rule to yield-stress and thixotropic systems, as described in his widely cited 1991 JoR paper. His more recent studies on blood rheology, such as his 2014 JoR paper and 2021 review in Soft Matter have advanced our fundamental understanding of red blood cell aggregation and dispersion in physiological flows, providing parameterized models that align closely with steady and transient experimental data, including new results for unidirectional LAOS (UD-LAOS) designed to mimic in vivo pulsatile flows.

Beyond classical systems, Antony has been at the forefront of modeling emerging materials. His work on “living polymers” in rodlike micellar systems brought the dynamics of micelle breakage and reformation into a thermodynamic context through stress-dependent reaction kinetics. His studies of liquid crystals culminated in the Beris-Edwards model, which reconciled and unified earlier theories into a consistent tensorial formulation. His exploration of emulsions, particularly with respect to micro-inertial effects, has offered foundationally new perspectives in this field. A hallmark of his research is the consistent comparison of new theory with leading experimental and simulation data, which has motivated him to also develop novel, powerful computational tools for optimization of parameter fitting by parallel tempering (AIChE J.) that find application in model reduction and simplification across a broad range of engineering science.

His scholarly output includes more than 150 refereed publications, a dozen of which have garnered over 150 citations each. He has delivered 188 invited lectures—including keynotes at international congresses—and 328 contributed presentations, primarily on rheology related topics. His expertise has been widely sought in rheology-related short courses, delivered across the U.S., Europe, and Asia, including notable venues such as the University of Louvain, the Institute of Mathematics and its Applications, the Kavli Institute of the Chinese Academy of Sciences, and most recently, the University of Patras. His outreach to the community includes coauthoring English language translations of classical papers by Geisekus.

Antony Beris has played a central role in community leadership, including the organization of major rheological meetings. He was the program chair for the 66th Annual Meeting of The Society of Rheology (1994), co-chaired the 78th meeting (2006), and has taught numerous international workshops on nonequilibrium thermodynamics and numerical methods for viscoelastic flows. Since 2009, he has served on the editorial board of the Journal of Non-Newtonian Fluid Mechanics and has been an active reviewer for all major fluid mechanics and rheology journals.

Equally important is Professor Beris’s legacy in education and mentorship. Over the years, he has inspired generations of undergraduate and graduate students through his teaching in fluid mechanics and applied mathematics. His former Ph.D. students have gone on to distinguished academic careers, including some leading academics well known to the rheology community: Lt Col. Matt J. Armstrong (ret. U.S. Military Academy), Brian J. Edwards, (Chem Eng. Univ. Tennessee); Kostas D. Housiada (Mathematics, University of the Aegean, Greece); Vlasis G. Mavrantzas, (Chem. Eng., University of Patras and ETH Zurich); R. (Suresh) Sureshkumar, Distinguished Professor (Syracuse), as well as postdocs including Univ.-Prof. Dr. Natalie German (Stuttgart) and Peter Wapperom (Mathematics, VPI), in addition to those who have impactful careers in industry, applying rheological and fluid dynamical insights to diverse sectors including advanced materials, polymers, and biomedical engineering.

Selective testimonials from his nominators underscore this impact, noting that Antony Beris “is a world leader in the fluid dynamics of complex fluids,” while also praising his development of a nonequilibrium thermodynamic framework as a “monumental achievement that continues to be required reading for researchers.” “Antony is so good and his work is so thorough,” citing “his originality, independence and deep thinking, which characterizes his research style.” Importantly, “Antony is an excellent teacher. He is able to communicate very difficult concepts to students in a way that they are able to understand them. Overall, he is committed to training the next generation of rheologists.” Antony is indeed a keystone in the bridge between nonequilibrium thermodynamics, rheological science, and applied rheology and engineering.

On a personal note, I joined UD in 1991 excited for the opportunity to work with Prof. Arthur Metzner and then Associate Prof. Antony Beris. In the early 90s Antony was working intensely with then PhD student Brian Edwards on the aforementioned book, which was facilitated by teaching a graduate class that I and one of my first doctoral students, Lynn Walker (now Prof. of U. Minn.) boldly endeavored to learn. This seminar class often consisted of Brian and Antony developing the foundational principles of nonequilibrium thermodynamics and working out the bracket formulation for specific applications on the chalk board. We were privileged witnesses to the (sometimes contentious!) birth of a landmark piece of scholarship. Over the past decades at Delaware I have had the honor and pleasure to continue to grow and learn from Antony, including co-mentoring multiple doctoral students and taking deep dives into nonequilibrium thermodynamics and then exploring its practical manifestations. For the past decade, we have endeavored to develop a theoretical and experimental understanding of the rich and complex thixotropic behavior of human blood by co-mentoring a cadre of exceptional students, which also facilitated developments in suspension rheology as detailed in a recent book chapter by Antony (“Hemorheology”, in Theory and Applications of Colloidal Suspension Rheology, Cambridge Univ. Press, 2021). Always innovating his teaching and research, Antony is developing machine learning tools to advance rheological constitutive equations and more specifically, hemorheology.

With this award, The Society of Rheology honors not only Antony Beris’s deep and sustained scientific excellence but also his lasting influence on the field’s intellectual foundation and future direction. His scholarship exemplifies the depth, rigor and vision that the Bingham Medal is intended to celebrate. A proud father of Zoe (currently a UD physics student) and Nicholas, Antony and his wife Sophia (see photo accompanying this article in Rheology Bulletin, Vol. 94 No. 1, Aug 2025) continue the Metznerian traditions of thoughtful and dedicated teaching and mentoring of the next generation of rheologists, as well as attracting international scholars that enrich our academic community and quickly become members of the international family of Delaware rheologists.