Affiliation: KU Leuven (Belgium)
Bio:
Pierre-Thomas Brun received his bachelor’s degree in Mechanical Engineering from École Polytechnique, Palaiseau in 2008, his Master’s degree in Advanced Chemical Engineering from the University of Cambridge in 2009, and his PhD in Mechanical Engineering from Sorbonne University in 2012 for work on the dynamics and instability of viscous and elastic threads. He then joined the École Polytechnique Fédérale de Lausanne (EPFL) as a postdoctoral fellow, where he specialized in interfacial fluid mechanics and instabilities. In 2014, he joined the Massachusetts Institute of Technology (MIT) as an instructor in Applied Mathematics. He moved to Princeton University in 2017, joining the Department of Chemical and Biological Engineering, where he was promoted to Associate Professor with tenure in 2024. In 2025, he returned to Europe to join the Department of Chemical Engineering at KU Leuven. His research is curiosity-driven and focuses on the quantitative modeling of nonlinear fluid and elastic processes in complex soft materials, as well as on the mathematical description of structure formation in inert and biological systems. His work is highly interdisciplinary and closely integrates theory, modeling, and experiments.
Title:
From Instability-Driven Fabrication to Soft Robotics: A Mechanics-First Approach
Abstract:
A central theme of our research is that interfacial flows and mechanical instabilities offer powerful and scalable routes for generating structure and function in soft materials. Through studies of viscous–elastic coupling in curable liquids and nonlinear deformation in slender bodies, we have shown how controlled buckling, coiling, and pattern formation can be harnessed as both fabrication tools and mechanisms for complex actuation and motion. I will discuss how these instability-based principles have enabled emerging applications ranging from programmable filaments to deployable architectures and smart elastoactive structures. Advances in modeling, fabrication, and materials characterization have reshaped the landscape of instability engineering, revealing new opportunities and challenges in using mechanics as a design language for robust, adaptive, and scalable soft robotic systems.
Affiliation: Polytechnic University of Bari (Italy)
Bio:
Stefania Cherubini is Full Professor at the Polytechnic University of Bari. In 2010, she obtained a joint Italian PhD in Machinery Engineering from the Polytechnic University of Bari and a French PhD in Mechanics from Arts et Métiers ParisTech. She was finalist for the Leonardo da Vinci Award of ERCOFTAC for her PhD thesis. From 2012, she was Assistant Professor at the DynFluid Laboratory of Arts et Métiers ParisTech, and in 2015 she received the AIMETA Junior Prize for Fluid Mechanics, awarded by the Italian Association of Theoretical and Applied Mechanics. Since 2016, she has been Professor of Fluid Machinery at the Polytechnic University of Bari. Her research focuses on understanding and modeling instabilities and coherent structures in transitional and turbulent flows, with applications including drag reduction through rough surfaces and energy harvesting from fluid flows.
Title:
The Emergence of Large-Scale Spatial Modulations in Turbulent Channel Flow
Abstract:
Large-scale coherent structures are frequently observed in turbulent channel flows, both at high Reynolds numbers and in transitional regimes preceding laminar–turbulent pattern formation. In both cases, the origin of such spatial modulations remains an open question. In this talk, a possible mechanism for the emergence of large-scale structures is proposed, interpreting them as secondary instabilities of small-scale streaks. The problem is addressed numerically through linear stability analysis, considering a base flow composed of the mean flow and coherent streaks. The results show that this flow becomes unstable to large-scale modulations whose structure, critical Reynolds number, orientation, and wavelength agree well with observations from the literature. The role of eddy viscosity is discussed through an energy budget analysis, and a nonlinear model is proposed to explain the persistence of laminar–turbulent patterns.
Affiliation: University of California, Santa Barbara (USA)
Bio:
Eckart Meiburg received his PhD in Mechanical Engineering from the Technical University of Karlsruhe in Germany in 1986. After a postdoctoral stay at Stanford University and faculty appointments at Brown University and the University of Southern California, he joined the University of California, Santa Barbara in 2000, where he is currently Distinguished Professor of Mechanical Engineering. He is a recipient of the NSF Presidential Young Investigator Award and the Humboldt Senior Research Award, a Fellow of the American Physical Society and the American Society of Mechanical Engineers, a former Chair of the APS Division of Fluid Dynamics, and an Associate Editor of Physical Review Fluids. He has held visiting positions in France, Switzerland, Australia, New Zealand, Germany, and Israel. His research interests lie broadly in fluid dynamics and transport phenomena, with particular emphasis on multiphase and environmental fluid mechanics.
Title:
Fluid Mechanics of the Dead Sea: Rise of the Salt Giants
Abstract:
The Dead Sea provides a unique environmental setting in which buoyancy-driven flows, phase change, and sedimentation processes interact in ways not observed elsewhere on Earth. As a terminal lake with salinity close to saturation, precipitation and dissolution processes are tightly coupled to fluid motion, leading to continuous halite deposition. During summer, thermohaline stratification produces descending supersaturated salt fingers that precipitate halite, while in winter the well-mixed water column generates salt throughout its depth. Rapid lake-level decline exposes vast new shoreline areas, carved by streams into deeply incised channels. Together, these phenomena offer insight into the formation of ancient salt giants and provide lessons for understanding coastal stability and erosion under changing sea levels.
Affiliation: ETH Zurich (Switzerland)
Bio:
Nicolas Noiray is Associate Professor at ETH Zurich, where he founded the Combustion, Acoustics and Flow Physics (CAPS) Laboratory in 2014. He received his PhD from École Centrale Paris in 2007 and subsequently worked in the Gas Turbine Research Division of Alstom. His research combines theoretical, experimental, and computational approaches to study combustion, acoustics, and fluid mechanics, addressing both fundamental and applied problems. He has received several prestigious awards, including the Silver Medal and the Hiroshi Tsuji Early Career Researcher Award of the International Combustion Institute, as well as ERC Consolidator and Synergy Grants. A central theme of his work is the modeling and control of instabilities across a wide range of time and length scales.
Title:
Fascinating Aeroacoustic Instabilities in Spinning-Wave Whistles
Abstract:
This talk explores aeroacoustic instabilities in axisymmetric whistles, focusing on spinning acoustic modes rather than the standing-wave oscillations typical of classical wind instruments. Using a combination of experiments, particle image velocimetry, stochastic modeling, large-eddy simulations, and linearized Navier–Stokes analysis, we investigate the coupling between helical hydrodynamic modes and spinning acoustic waves. Different symmetry-breaking mechanisms and bifurcations are discussed, including transitions between intermittently reversing and stable spinning states, as well as the emergence of mean swirl induced by aeroacoustic limit cycles.
Affiliation: University College London (United Kingdom)
Bio:
Helen Wilson is Professor of Applied Mathematics at University College London and former Head of the UCL Department of Mathematics. She obtained her PhD from the University of Cambridge in 1998 and held positions at the University of Colorado and the University of Leeds before joining UCL. She has published nearly 50 papers on the flow of complex fluids and has played a leading role in the rheology community. She served as President of the British Society of Rheology (2015–2017) and as Vice-President of the Institute for Mathematics and its Applications (2019–2020). She is an editor of the Journal of Non-Newtonian Fluid Mechanics and Proceedings of the Royal Society A, and currently chairs the Nominating Committee for ICMS and the Scientific Steering Committee of the Isaac Newton Institute.
Title:
Instabilities in Viscoelastic Fluids
Abstract:
Many industrial fluids possess complex microstructures that lead to viscoelastic behavior, allowing them to store and release elastic energy during flow. This can give rise to a wide range of instabilities, often with undesirable consequences. This talk reviews the modeling of viscoelastic fluids, including polymer solutions and melts, and examines how viscoelasticity affects flow stability. After discussing well-understood mechanisms such as curved-streamline instabilities, shear banding, and interfacial instabilities, the focus shifts to flows with straight streamlines, where instability mechanisms remain less understood. Open challenges and directions for future research are highlighted.