ANR Chair of Excellence TUCOROM (2010-2015) by Bernd NOACK

The ANR Chair of Excellence 'Closed-loop control of turbulent shear flows using reduced-order modelling (TUCOROM)' has fueled and finally enabled a long-term dream of mine: a generally applicable method for a feedback control logic for real-world turbulence. We have termed this method 'Machine Learning Control (MLC)'. Additional enablers for feedback turbulence control include Cluster-based Reduced-Order Modelling (CROM) and progresses on POD-based Reduced-Order Modelling (ROM) Exemplary publications include:

• Brunton, S. L. & Noack, B. R. (2015) "Closed-loop turbulence control: Progress and challenges". Applied Mechanics Reviews (online). (html)
• Gautier, N., Aider, J.-L., Duriez, T., Noack, B. R., Segond, M. & Abel, M. W. (2015) "Closed-loop separation control using machine learning". Journal of Fluid Mechanics 770, 242-441 (html)
• Kaiser, E. Noack, B.R., Cordier, L., Spohn, A., Segond, M., Abel. M., Daviller, G., Östh, J., Krajnovic, S., & Niven, R.K. (2014) "Cluster-based reduced-order modelling of a mixing layer". J. Fluid Mech. 754, 365-414. (html) (pdf)
• Noack, B.R., Morzynski, M. & Tadmor, G. (eds.) (2011) "Reduced-Order Modelling for Flow Control," CISM Courses and Lectures 528, Springer-Verlag. (html)

On this webpage, I want to acknowledge the invaluable contributions of many friends and colleagues making this happen. First of all, I am deeply grateful to the French Agence Nationale de la Recherche (ANR) for providing me such a Chair of Excellence as generous flexible funding vehicle. This was a warm welcome for my relocation to France. Second, my employeer, the French National Research Foundation (CNRS) provides me all professorial rights and unparalleled academic freedom for my work. A Director of Research CNRS is truly a dream position. Third, I am indepted to Profs. Markus ABEL, Steven BRUNTON and Rolf RADESPIEL for providing us intellectual homes for developping new control methods and experiments in Potsdam (Germany), Brunswick (Germany) and Seattle (USA), respectively.

Early preparatory work (1988-2010)

The project was prepared more than two decades in advance. I am deeply grateful to my mentors on the long journey.

• My PhD father Helmut ECKELMANN (MPI für Strömungsforschung) has polished my talents and deeply invested in me as my first living role-model, mentor and friend. Under him, I have learned to appreciate a working experiment, the exciting atmosphere of a family-type research group, and the value of polished Journal publications.
• Andrzej BANASZUK (UTRC) has introduced me to the exciting world of industrial applications and modern control theory. He has always emphasized that the 'control theory of turbulence still needs to be invented'. The joined work at UTRC has laid the road map for the following work until now.
• Andreas DILLMANN (TU Berlin -2003, now DLR) and Rudibert KING (TU Berlin) have mentored my career at TU Berlin under the excellent conditions of the Collaborative Research Center (SFB 557) "Control of complex turbulent shear flows". Our successful 'C5' project 'Low-dimensional modelling and control of turbulent shear flows' laid the groundwork of much of our current work.
• William K GEORGE (Chalmers, Imperial, Princeton, ...) has accompanied my career for almost a decade as an inspiring role model for turbulence research and networking "WikiThink" and as a friend.

Since the late 90's I have enjoyed a close collaboration with Marek MORZYNSKI (Poznan, Poland) and Gilead TADMOR (Boston). Day and night we have had discussion about many ideas and many joint projects, leading to my most cited publications.

ANR Chair of Excellence (2010-2015)

The work of the Chair of Excellence has been shaped by many PhD students, PostDocs, academic and industrial colleagues. I count over 100 co-authors during 2010-2014. I try to bring some order in my acknowledgments by introducing contributors in terms of distance from Poitiers and in alphabetically order.

Poitevin TUCOROM team (local colleagues)

• Jean-Paul BONNET and Yves GERVAIS have supported my relocation and dream CNRS position in France. Jean-Paul has also pushed the TUCOROM mixing-layer demonstrator.
• Jacques BOREE has initiated the OpenLab PPRIME/PSA enabling a fruitful collaboration with Peugeot-Citroën on open- and closed-loop drag reduction of car models.
• Laurent CORDIER was involved in many of my projects.
• Joel DELVILLE and Carine FOURMENT have build up the TUCOROM mixing-layer control demonstrator. Sadly, both have died in a tragic car accident, too early to see the fruits and impact of their first feedback turbulence work.
• Tamir SHAQARIN is not from Poitiers, but he has spend many months here. He has invested his large expertize in the actuation system of TUCOROM demonstrator and explored a number of traditional control strategies
• Andreas SPOHN has supported all experimental activities and has co-initiated the successful ANR SepaCoDe and PIRE projects.

Poitevin TUCOROM PostDocs

• Thomas DURIEZ was an outstanding PostDoc. Within few months he has developped the first show-cases of machine learning control (MLC) from dynamical systems, to direct numerical simulations and to several experiments in France. He has lead the MLC implementations at PPRIME, PMMH, PRISM, LML.
• Jean-Charles LAURENTIE has tamed the CONCURRENT data acquisition system and shaped the first MLC experiments.
• Vladimir PAREZANOVIC's role for our first TUCOROM mixing layer demonstrator can hardly be underestimated. On the fire-line between open-loop protagonists and feedback control advocates, he has improved the TUCOROM flag-ship experiment and lead our first MLC experiments to success.
• Michael SCHLEGEL's mathematical genius has lead to a number of exciting results, e.g. the first criterion for boundedness of ROM and ROM-based control solutions (Schlegel & Noack 2015 JFM).

Poitevin PhD students in TUCOROM and off-spring projects

• Diogo Barros (OpenLab PPRIME/PSA) has pioneered drag reduction of car models with high-frequency Coanda blowing. The resulting drag reduction for the square Ahmed body were unprecedented 20%!
• Eurika KAISER has developed cluster-based reduced-order modelling (CROM). This is the first data-driven framework solving the Liouville equation, or, equivalently, the Hopf (1952) formalism. We have first promising applications to strongly nonlinear control following Brocket's (1999) visionary paper.
• Kai von KRBEK has successfully worked on implementing MLC for separation control at Institut PRISME, Orléns, France and drag reduction at TU Braunschweig (under Dr. Richard SEMAAN). He currently works on MLC-based drag reduction under supervision of Prof. Robert MARTINUZZI (Calgary).
• Ruiying LI (OpenLab PPRIME/PSA) has joined us recently and pushes MLC in drag reduction of car models.
• Charles PIVOT (Region Poitou-Charentes) has joined us recently working on reinforcement learning for control.
• Gilles TISSOT (Region+ENSMA -2014) has successfully worked on ROM-based wake stabilization with 4D VAR methods and DMD variants.

French TUCOROM collaborators

• Jean-Luc AIDER and Nicolas GAUTIER (PMMH Paris) have lead the first MLC experiment of a wall-bounded shear layer (Gautier et al. 2015 JFM).
• Azeddine KOURTA, Nicolas MAZELLIER (PRISME, Orléns) and Michel STANISLAS (LML, Lille) enabled two new MLC experiments via the ANR SepaCoDe project.
• Tony RUIZ and Fabien HARAMBAT (PSA, Velizy) co-supervise MLC experiments for drag reduction of car models.

International TUCOROM team for MLC

• Markus ABEL (Potsdam) has introduced us to the world of machine learning methods in 2013, starting with the 'International Fori of Turbulence and Network Control (IFTNC-1, IFTNC-2)'. Few months after the first ideas, we had the first feedback control demonstrations of MLC in dynamical systems, DNS and the TUCOROM mixing-layer experiments thanks to outstanding team of Poitevin and Potsdam PostDocs: Thomas DURIEZ (now: CONICET), Jean-Charles LAURENTIE (now: U Montepellier), Vladimir PAREZANOVIC (Poitiers) and Marc SEGOND (now: Spain). Another exciting IFTNC result was CROM lead by Eurika KAISER (Poitiers/Florida).
• Steven BRUNTON (Seattle) has co-supervised the first control studies in the TUCOROM mixing-layer experiment and Hydra II water-tunnel. He has implemented various control theory approaches. Since then, he has shaped the TUCOROM project with a rich portefolio of control and machine learning methods and giving us a new intellectual refuge for joint work in Seattle.
• Rolf RADESPIEL, Peter SCHOLZ and Richard SEMAAN (TU Braunschweig) are providing us a new platform and intellectual home for feedback turbulence control experiments in Brunswick, Germany.

International TUCOROM team for ROM

• Maciej BALAJEWICZ (now: UIUC) has introduced us to a new subgrid closure based on a rotation of the subspace. See, e.g. Balajewicz et al. 2013 JFM.
• With Zach BERGER, Mark GLAUSER, Jacques LEWALLE and Kerwin LOW (Syracuse U) we have explored reduced-order modelling for jet noise control. See, e.g. Berger et al. 2015 FTC.
• Sinisa KRAJNOVIC and Jan ÖSTH (Chalmers) have accompanied our drag reduction experiments of cars with LES and the first POD model of a high-Reynolds number flow around an Ahmed body (Östh et al. 2014 JFM).
• Robert MARTINUZZI, Jason BOURGEOIS and Zara HOSSEINI (U Calgary) have played a principal role in our experimental reduced-order modelling activities (Bourgeois et al. 2014 JFM, Hosseini et al. 2015 EF). Robert is now developping a new feedback wake stabilization experiment.
• Robert NIVEN (UNSW) has introduced us to the world of maximum entropy principles and Bayesian inference. One outcome is a MaxEnt closure of Galerkin systems (Noack & Niven 2012 JFM, 2013 CAM). Control applications are explored in a joint ARC project.
• Bartosz PROTAS (McMaster) has pushed reduced-order modelling with the first 4D VAR identification of constitutive equations (complete functions, not parameters). The applications include dynamical systems (Protas et al. 2013 JNS) and subgrid turbulence closures (Protas et al. 2014 JFM).
See the list of publication for all published contributions.

TUCOROM collaborators and visitors

We have immensely profited from our many visitors. Many ideas and publications were developed or at least initiated during their visit.

Visitors of 2014

• Yang WANG (Invited researcher, 2014-10-29..11-01)
  • Seminar: "Climate network reveals and predicts climate variability and teleconnections"
    (2014-10-30, 14:15h, CEAT)
• Kevin WEBSTER (Invited researcher, 2014-10-15..17)
  • Seminar: "Approximation of Reachable Sets using Optimal Control and Support Vector Machines"
    (2014-10-16, 14:15h, CEAT)
• Thomas DURIEZ (Invited researcher, 2014-10-01..30)
• Steven Hendry Waldrip (Invited researcher, 2014-09-15..11-30)
  • Seminar: "Maximum Entropy Analysis of Hydraulic Pipe Networks"
    (2014-10-09, 14-16h, CEAT)
• Florimond GUENIAT (Invited speaker)
  • Seminar: "Coherent structures, feature points and mixing"
    (2014-06-19, 14-16h, CEAT)
• Gregg ABATE (Invited researcher 2014-06-13)
  • Seminar: "International Science Program & EOARD Overview"
    (2014-06-14, 10-11h, CEAT)
• Tamir SHAQARIN (Invited Professor, 2014-06-01..30)
• Bartek PROTAS (Invited Professor, 2014-04-21..27)
• Robert K. NIVEN (Invited Professor, 2014-03-08..12-20)
  • Seminar: "TBA"
    (2014-05-??, 14-16h, CEAT)
• Jan ÖSTH (Invited researcher, 2014-02-10..19)
• Kai von Krbek (Invited researcher, 2014-02-03..08-01)
  • Seminar: "Machine learning control - a literature review"
    (2014-03-05, 14-16h, CEAT)
  • Seminar: "Wave transmission through a chain of nonlinear oscillators"
    (2014-03-06, 14-16h, CEAT)

Visitors of 2013

• Olivier CADOT (Invited speaker, 2013-11-29)
  • Seminar: "Reflectional symmetry breaking modes of the flow past parallelepiped bodies"
    (2014-04-22, 14-16h, CEAT)
• Zachary Philip BERGER (Invited researcher, 2013-08-19..30)
• Helmut ECKELMANN (Invited researcher, 2013-07-15..19)
• Steven BRUNTON (Invited researcher, 2013-07-14..18)
• Luc PASTUR (Invited seminar speaker, 2013-07-09)
  • Seminar:Time-delayed feedback control for experimental flows
    (2013-07-09, 14-16h, LEA/SP2MI)
• Bartek PROTAS (Invited researcher, 2012-06-30..07-05)
• Shervin BAGHERI (Invited seminar speaker, 2013-06-24..28)
  • Seminar:Koopman modes for analysis of fluid flows
    (2013-06-25, 14-16h, LEA/SP2MI)
• Marc SEGOND (Invited researcher, 2013-06-23..28)
• Steven BRUNTON (Invited researcher, 2013-06-23..27)
• Bartosz PROTAS (Invited researcher, 2013-06-14..16)
• Lutz LESSHAFT (Invited seminar speaker, 2013-06-11)
  • Seminar:Instability-based approaches to aeroacoustic modeling.
    (2013-06-11, 14-16h, LEA/SP2MI)
• Marc SEGOND (Invited researcher, 2013-06-02..8)
  • Seminar:TBA
    (2013-06-05, 14-16h, CEAT)
• Simone CAMARRI (Invited seminar speaker, 2013-06-04)
  • Seminar:Global stability and sensitivity analysis of numerical and experimental flow fields with focus on flow control
    (2013-06-04, 14-16h, LEA/SP2MI)
• Tamir SHAQARIN (Invited researcher, 2013-05-24..07-10)
  • Seminar: TBA
    (2013-06-??, 14-16h, LEA/SP2MI)
• Maciej BALAJEWICZ (Invited senior researcher, 2013-05-11..05-22)
  • Seminar:Model order reduction of unsteady fluid-structure interactions
    (2013-05-14, 14-16h, LEA/SP2MI)
• Sinisa KRAJNOVIC (Invited senior researcher, 2013-05-01..07-30)
  • Seminar: Numerical investigations of flow instabilities and passive flow control mechanism around generic vehicle bodies"
    (2013-05-21, 14-16h, LEA/SP2MI)
• Jan ÖSTH (Invited researcher, 2013-05-01..07-30)
• Steven BRUNTON (Invited researcher, 2013-04-13..21)
  • Seminar: Reduced order unsteady aerodynamic models for closed-loop feedback control
    (2013-04-17, 14-16h, LEA/SP2MI)

Visitors of 2012

• Michael SCHLEGEL (Invited researcher, 2012-12-10..14)
• Robert NIVEN (Invited senior researcher, 2012-11-28..12-16)
  • Seminar: Maximum Entropy Analysis of Steady-State Flow Systems
    (2012-12-07, 14-16h, CEAT)
• Richard SEMAAN (Invited seminar speaker, 2012-11-22..24)
  • Seminar: Fundamentals of high-lift for future commercial aircraft, Overview of the Collaborative Research Centers SFB 880
    (2012-11-23, 14-16h, CEAT)
• Sinisa KRAJNOVIC (Invited senior researcher, 2012-11-04..5)
• Jan HEILAND (Invited researcher, 2012-10-07..10-14)
  • Seminar: Two Approaches to Optimal Control of Linearized Navier-Stokes Equations - I. Direct Discretization of the Input to Output Behavior and II. Generalized Riccati Equations
    (2012-10-10, 14-16h, CEAT)
• Razvan STEFANESCU (Invited researcher, 2012-09-03..09)
  • Seminar: Trust region adaptive POD/DEIM 4D-Var for a finite-element shallow water equations model
    (2012-09-03, 14-16h, LEA/SP2MI)
• Robert MARTINUZZI (Invited researcher, 2012-07-15..08-14)
• Marcin CHRUST (Invited speaker, 2012-07-09..07-11)
  • Seminar: Direct Numerical Simulation of the dynamics of falling disks
    (2012-09-10, 14-16h, LEA/SP2MI)
• Gregor GILKA (Invited researcher, 2012-07-08..07-15)
• Jason BOURGOIS (Invited researcher, 2012-06-24..07-06)
• Sinisa KRAJNOVIC (Invited speaker, 2012-06-24..26)
  • Seminar: Large Eddy Simulation: A tool for understanding of vehicle flows
    (2012-06-25 14:00, LEA/SP2MI)
• Thomas DURIEZ (Invited speaker, 2012-06-07..8)
  • Seminar: Boundary layer and shear flow manipulation using DBD plasma actuator.
    (2012-06-08, 10:30, CEAT)
• Ionel Michael NAVON (and R. STEFANESCU) (Invited speaker, 2012-06-01..06-05)
  • Seminar: POD/DEIM nonlinear model reduction and POD/4-D VAR with TRUST-region and dual weighting for models of the shallow water equations
    (2012-06-04, 14-16h, LEA/SP2MI)
• Tamir SHAQARIN (Invited researcher, 2012-06-01..09-15)
  • Seminar: Closed loop active separation control for a thick turbulent boundary layer
    (2012-06-19, 14-15h, CEAT)
• Kerwin LOW (Invited researcher, 2012-06-01..07-30)
  • Seminar: Subsonic jet noise: Part I: Progress towards the understanding of jet noise through shear layer excitation
    (2012-06-25, 14:00-15:30, CEAT)
• Eurika KAISER (Invited researcher, 2012-06-01..06-30)
• Jacques LEWALLE (Invited researcher, 2012-06-01..06-30)
  • Seminar: Subsonic jet noise: Part II: Progress toward the description of sources
    (2012-06-25, 15:30-17:00h, CEAT)
• Nicholas KEVLAHAN (Invited speaker, 2012-03-27)
  • Seminar: A brief introduction to wavelet methods for the analysis and computation of turbulent flows
    (2012-03-27, 14-16h, CEAT)
• Jose-Eduardo WESFREID (Invited speaker, 2012-03-20)
  • Seminar: Les structures cohérentes dans la transition à la turbulence et le contrôle des écoulements
    (2012-03-20, 14-16h, LEA/SP2MI)
• Eurika KAISER (Invited researcher, 2012-03-13..16)
• Maciej BALAJEWICZ (Invited researcher, 2012-03-01..31)
  • Seminar: A new approach to model order reduction of the Navier-Stokes equations
    (2012-03-06, 14-16h, CEAT)
• Bartek PROTAS (Invited researcher, 2012-02-18..03-31)
  • Seminar: Optimization as a paradigm for probing fundamental bounds in Turbulence research
    (2012-02-22, 14-16h, LEA/SP2MI)
  • Lecture: Computational methods for optimal control for differential equations I
    (2012-03-05, 10-12h, CEAT/Salles des Actes)
  • Lecture: Computational methods for optimal control for differential equations II
    (2012-03-05, 14-16h, CEAT/Salles des Actes)

Visitors of 2011

• Vladimir PAREZANOVIC (Invited speaker, 2011-12-08)
  • Seminar: Experimental study of the sensitivity of global properties of turbulent bluff body wakes using steady disturbance methods
    (2011-12-08, 11-12h, CEAT)
• Jorge BAILON-CUBA (Invited researcher, 2011-11-28..12-03)
  • Seminar: POD models for turbulent convection in rectangular cells
    (2011-11-30, 11-12h, CEAT)
• Michael SCHLEGEL (Invited researcher, 2011-10-17..28)
• Ingrid HOTZ (Invited speaker, 2011-10-17..19, CEAT)
  • Seminar: Flow Feature Extraction from a Data Analysis Point of View
    (2011-10-18, 14-16h, CEAT/Salle des Actes)
• Angelo IOLLO (Invited speaker, 2011-09-20)
  • Seminar: Modal representation for reduced order models
    (2011-09-20, 14-16h, LEA/SP2MI)
• Hans-Christian HEGE (Invited researcher, 2011-09-19..26, CEAT)
  • Seminar: Visualising quantified uncertainty
    (2011-09-??, 14-16h, LEA/SP2MI)
• Denis SIPP (Invited speaker)
  • Seminar: Open-loop control of instabilities in open flows
    (2011-09-13, 14-16h, LEA/SP2MI)
• Jason BOURGOIS (Invited researcher, 2011-09-01..30, CEAT)
• Aniruddha SINHA (Invited researcher, 2011-06-19..26, CEAT)
  • Seminar: Development of feedback control for high speed jets
    (2011-06-21, 14-16h, LEA/SP2MI)
• Jens KASTEN (Invited researcher, 2011-06-05..11, CEAT)
  • Seminar: On the extraction and filtering of Lagrangian features based on the acceleration
    (2011-06-07, 14-16h, LEA/SP2MI)
• Gilead TADMOR (Invited researcher, 2011-06-04..17, CEAT)
  • Seminar: To be announced
• Sergey OLADYSHKIN (Invited speaker, 2011-05-15..17, CEAT)
  • Seminar: Bayesian Updating on Arbitrary Polynomial Chaos Expansion: Application to Carbon Dioxide Storage in Geological Formations (2011-05-16, 14-16h, LEA/SP2MI)
• Michael SCHLEGEL (Invited researcher, 2011-05-01..13, CEAT)
  
• Seminar 1: Kraichnan''s Direction Interaction Approximation. Prelude: Renormalized Pertubation Theories
  (2011-05-04, 14-17h, CEAT)
• Seminar 2: Kraichnan''s Direction Interaction Approximation. Ideas, Failures and Successes.
  (2011-05-06, 14-17h, CEAT)
• Seminar 3: Kraichnan''s Direction Interaction Approximation. Epilogue: Extensions
  (2011-05-09, 14-17h, CEAT)
• Jens KASTEN (Invited researcher, 2011-04-24..30, CEAT)
  
  • Seminar: On the extraction and filtering of Lagrangian features
    (2011-05-26, 14h CEAT)
• Marek MORZYNSKI (Invited researcher, 2011-04-04..14, CEAT)
  
• Markus ABEL (Invited Professor, 2011-04-01..06-30, CEAT)
  
  • Seminar 1: Dimension reduction tools
    (2011-05-02, 9-12h, CEAT)
  • Seminar 2: Fluctuations of thermodynamic systems in finite time
    (2011-05-03, 9-12h, CEAT)
  • Seminar 3: Turbulence characterization: Entropies, dimensions and in how far they have reduced meaning for some applications
    (2011-05-04, 9-12h, CEAT)
• Robert NIVEN (Invited senior CNRS researcher, 2011-03-05..06-01, CEAT)
  
  • Seminar 1: The Maximum Entropy Method of Jaynes
    (2011-03-21, 14-17h, CEAT)
  • Seminar 2: Application of MaxEnt to Steady-State Flow Systems (and Extremum Entropy Production Principles)
    (2011-03-22, 14-17h, CEAT)
  • Seminar 3: Further Applications of MaxEnt to Steady-State Flow Systems
    (2011-03-23, 14-17h, CEAT)