1. A Simulation Framework for Testing Flow Control Strategies Marek Gayer, Milan Milovanovic and Ole Morten Aamo Faculty of Information Technology, Mathematics and Electrical Engineering Department of Engineering Cybernetics The 18th IASTED International Conference on Applied Simulation and Modelling ~ASM 2009 September 7 – 9, 2009 Palma de Mallorca, Spain http://www.itk.ntnu.no

2. Introduction 1/2: Flow control of vortex shedding around 2D cylinder 2ASM 2009

3. Introduction 2/2: Flow control with suction/blowing actuation slots 3ASM 2009

4. Post-processing Results Flow control module Simulation case VISTA with Diffpack Navier-Stokes solver and data Utility library Grid Actuation --- Feedback Simulation framework architecture ASM 20094

5. Code VISTA – CFD/N-S solver Finite element method based incompressible Navier-Stokes solver C++, using Diffpack numerical package VISTA menu system reads parameters from extendible input case files Additional parameters provided in files Support for computational grids, VTF data sets, restarting simulations 5ASM 2009

6. Flow control modules Realizes simulation of a flow controller Reads data for a control case Reads variables from N-S CFD code Implement a controller computation Applies computed values back to N-S Output results to files Implemented as inherited C++ classes 6ASM 2009

7. Utility Library Provides general functionality for Flow Control modules Uses VISTA and Diffpack Routines for real and complex matrix and vector classes Reading and writing data files Uses special.m files for input/output 7ASM 2009

8. Simplified Ginzburg-Landau equation for, with boundary conditions and Stabilizing state feedback controller: Case study: Control of vortex shedding around cylinders with G-L 8ASM 2009

9. Curves along which A – transversal velocities are measured 9ASM 2009

10. Computational grid for VISTA CFD 10ASM 2009

11. Stabilization of fully developed vortex shedding; Re=60 (GL Inova) 11ASM 2009

12. Suppression of transversal velocities 12ASM 2009

13. Monitoring of simulation control related parameters in MATLAB 13ASM 2009

14. 3D plot of pressures around the cylinder boundary (±180º) 14ASM 2009

15. Conclusion Simulation Framework for incompressible fluid flow control featuring: –CFD code VISTA (Navier-Stokes based) –Flow Control Module(s) –Utility Library –Input cases with grid input files Results visualized/real time monitored in MATLAB and GL Inova Case study removes vortex sheddding;Re=60 15ASM 2009

16. 16ASM 2009 Possible future effort Extend to work with the output feedback problem, for the G-L eq. in [Aamo2007] Try for Re > 60 Develop simulation cases and modules for 3D control of fluid flows Implement parallel processing

17. 17ASM 2009 Thank you for your attention. ?????? Do you have any questions ?