CIMNE

1. Fluid-Structure Interaction for Combustion Systems 30-Months Progress Meeting Siemens Power Generation Mulheim, Germany June 14 CIMNE

2. Pavel Ryzhakov - Curriculum Vitae June 1999 – Graduated from High-School of Physics and Technology, Saint-Petersburg, Russia Dec 2004 – BSc in Mechanical Engineering, University of Karlsruhe, Germany, scholarship by Siemens AG Dec 2005 MSc in Computational Mechanics, Technical University of Munich, Germany, sponsored by Siemens AG Master thesis: “Error estimation and adaptivity for the fluid mechanics Problems” June 2005 – member of the Bavarian Elite Students Network February 2006 – PhD at CIMNE started

3. Work done/work in progress Adaptive mesh refinement techniques based on the subgrid models Fluid-Structure coupling-1 Fluid-Structure coupling-2

4. Subgrid scale energy:

5. Adaptive mesh refinement – flow over cylinder

6. Coupling Interpolator Library • Allows sharing information between two different FEM programs along the simulation. The library makes the variable interpolation between the different meshes used by the codes, so each code is written in a independent way. Sending and receiving the variables in their own nodes!!

7. Coupling Interpolator Library Structural code and fluid code are running independantly And the Coupling Library works just as a message passing library between the two independant processes (similar to MPI) When nodal values need to be updated, library functions are being Executed (send – receive concept).

8. Coupling Interpolator Library Structural FEM program CFD FEM program Coupling Interpolator Library Pressure on the mesh Nodal displacement Interpolate variables from Mesh 1 to Mesh 2 Interpolate variables from Mesh 2 to Mesh 1 Nodal displacement Pressure on the mesh

9. Coupling Interpolator Library The library allows a week coupling in a multi-physics problem simulation.

10. Coupling Interpolator Library The library permits communication between C and FORTRAN codes indistinctly. And the variables of communication depend exclusively of the FEM codes, so different problems can be solved. Fluid – Structure Magnetism – Structure Heat Transfer – Fluid even the same type of analysis like Structure - Structure

11. S2 F2 CSD CFD S1 S3 F1 F3 Linear interpolation - Oct-tree space partitioning to find “neighbours” e.g. if a node of structure is lying within a fluid element the value at this node (red) will be interpolated to the nodes of the respective element of the fluid and so on

12. Coupling Interpolator Library Example: Heat Transfer A moving hot cube warms a plate

13. Coupling Interpolator Library Fluid – Structure Problem. A vessel under pulsar pressure

14. Coupling Interpolator Library Interpolator Functions InitCouplingMesh InsertCouplingNodes InsertCouplingNewNodes InsertCouplingDisplacement InsertCouplingMesh WriteCouplingMeshOnFile

15. Coupling Interpolator Library Communication Functions InitCouplingLibrary InsertCouplingLibraryDDE SendCouplingDataF SendCouplingDataI RetriveCouplingHeader RetriveCouplingDataF RetriveCouplingDataI Asynchrony communication using TCP/IP protocol

16. Work in progress Use L2 projection of the origin field onto the destination one or in other words Imply the equality of the field variables along the boundary interface in a weak sense, i.e.

17. Advantages: - “conservation” of quantities along the interface boundary in an integral sense - possibility to work with non-matching meshes

18. Results: structure Test: Prescribed sinusoidal Pressure on the fluid side P=sin(x) Transfer pressure to the structure. fluid

19. pressure Results: structure fluid

20. Thank you for attention!