DDPS | ‘Regularized reduced order models for control of Navier-Stokes equations’

· DDPS Talk date: February 22, 2024
· Speaker: Francesco Ballarin (Università Cattolica del Sacro Cuore, www.francescoballarin.it/)
· Description: Numerical stabilization is often used to alleviate the spurious oscillations generally produced by full order models (FOMs) in under-resolved or marginally-resolved simulations of convection-dominated flows modelled by the incompressible Navier-Stokes equations. However, when dealing with reduced order models (ROMs) of convection-dominated, marginally-resolved flows, the role of numerical stabilization is still not well understood. Further challenges arise when interested not only in the simulation of the flow itself, but also on its control, for instance to achieve a desired target configuration.
The presentation will be divided in two parts, which discuss two different regularization techniques. In the first part of the talk, based on [1], we present an evolve-filter-relax regularized ROM and apply it to a feedback control problem. In the second part of the presentation we establish a novel regularized ROM, based on approximate deconvolution and introduced in [2].
[1] Maria Strazzullo, Francesco Ballarin, Traian Iliescu, and Claudio Canuto. 2023. “New Feedback Control and Adaptive Evolve-Filter-Relax Regularization for the Navier-Stokes Equations in the Convection-Dominated Regime.”
[2] Anna Sanfilippo, Ian Moore, Francesco Ballarin, and Traian Iliescu. 2023. “Approximate Deconvolution Leray Reduced Order Model for Convection-Dominated Flows.” Finite Elements in Analysis and Design 226: 104021.
· Bio: Francesco Ballarin graduated in Mathematical Engineering at Politecnico di Milano, defending his BSc thesis in 2009 and MSc thesis in 2011. He then pursued a PhD in Mathematical Models and Methods in Engineering at MOX, Department of Mathematics, Politecnico di Milano, defending his PhD thesis in 2015 under the supervision of Prof. Alfio Quarteroni. After his PhD, he has been post-doctoral research fellow (2015-2018) and Assistant Professor of Numerical Analysis (2018-2021) at SISSA mathLab in the group of Prof. Gianluigi Rozza. Since March 2021, Francesco is a Tenure-track Assistant Professor of Numerical Analysis at the Department of Mathematics and Physics, Università Cattolica del Sacro Cuore, Brescia, Italy. His research focuses in particular on reduced order methods (ROMs) for parametrized problems in computational fluid dynamics. He is author of more than 50 publications on numerical analysis, scientific computing and related topics. Francesco is also a passionate developer of open source software libraries (especially in C++ and Python), that become an integral part of his research activities.
DDPS webinar: www.librom.net/ddps.html
💻 LLNL News: www.llnl.gov/news
📲 Instagram: / livermore_lab
🤳 Facebook: / livermore.lab
🐤 Twitter: / livermore_lab
About LLNL: Lawrence Livermore National Laboratory has a mission of strengthening the United States’ security through development and application of world-class science and technology to: 1) enhance the nation’s defense, 2) reduce the global threat from terrorism and weapons of mass destruction, and 3) respond with vision, quality, integrity and technical excellence to scientific issues of national importance. Learn more about LLNL: www.llnl.gov/.
IM release number is: LLNL-VIDEO-860853