1 / 20

LES and URANS predictions using Star-CD V&V for T-Junction test case (Vattenfall Experiment)

France-Japan joint Seminar on Thermal fatigue, 5 th to 6 th October 2009, Tokyo, Japan. LES and URANS predictions using Star-CD V&V for T-Junction test case (Vattenfall Experiment) Part of UK’s “ K eeping N uclear O ptions O pen” project. Presented by: Y. Addad

meriel
Download Presentation

LES and URANS predictions using Star-CD V&V for T-Junction test case (Vattenfall Experiment)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. France-Japan joint Seminar on Thermal fatigue, 5th to 6th October 2009, Tokyo, Japan. LES and URANS predictions using Star-CD V&V for T-Junction test case (Vattenfall Experiment) Part of UK’s “Keeping Nuclear Options Open” project Presented by: Y. Addad Collaborators: A. Keshmiri, S. Rolfo, M. Cotton, D. Laurence School of Mechanical, Aerospace & Civil Engineering (MACE) The University of Manchester

  2. Rod Bundle arranged in a triangular array SFR fuel assembly Re=11,000 Liquid sodium Exp. f=13Hz The person to contact: www.cfd.mace.manchester.ac.uk/Main/StefanoRolfo

  3. Thermal mixing in T-Junction: Previous work:

  4. Experiment of thermal mixing in T-Junction Flow Ratio: Qc/Qh=2 T = 15°C DC=0.14 m, Dh=0.1m ReC=105 , Reh=105 Previous LES runs with Fluent (see reference) Reference: Westin J. et al. “High-Cycle Thermal Fatigue in Mixing Tees. Large-Eddy Simulations Compared to a New Validation Experiment”, 16thInt. Conf. On Nuclear Engineering (ICONE-16).

  5. Thermal mixing in T-Junction: Grid 3.1Dh 3Dc 13Dc Grid Cells= 2.56 M. LES RUNS: SGS Model: Smago. PrSGS=0.9 (Default). URANS RUNS: Non-linear k- model Suga et al. 2006. Numerical schemes: 2nd order in space. 2nd order in time.

  6. Inlet Boundary conditions (cyclic RANS) Hot Cold Hot Cold

  7. Instantaneous Temperature variation LES versus URANS LES run Experiment URANS run

  8. Time-averaged V & Temp. in cross sections Plan 2.6D Plan 6.6D URANS Recirculation LES

  9. Velocity Profiles at the plan x=2.6D z 2.6D x

  10. z 2.6D x Velocity fluctuations Profiles at the plan x=2.6D

  11. Velocity Profiles at the plan x=6.6D z 6.6D x Resolved part only

  12. Temperature Profiles at the plan x=6.6D z 6.6D x

  13. Z T Y L R B T variation at 1mm from walls along the x axis.

  14. LES LES U URANS URANS W

  15. Z T Y L R B Trms variation at 1 mm from walls along the x axis

  16. Z Y Centre Variation of the velocity fluctuations along the x axis in the centre.

  17. Time history of temperature near the walls Z 2 Y 3 1 4 Probe1 Probe3 Probe2 Probe4

  18. Spectra of temperature near the walls Z 2 Y 3 1 4

  19. Z 2 Y 3 1 4 Spectra of streamwise velocity near the walls.

  20. - URANS model: - Fails to capture the complex features of the flow. - Most information needed for thermal fatigue studies is lost. - Not able to capture high frequency events. - Can this be improved or other approaches tested (example DES) ?? - LES with Unstructured grids and Professional Software: - Second order accuracy seems OK. • Mesh is extremely important, adapted to (1/10) large eddy scale ? => need unstructured mesh • Work in progress: How about tetrahedral and polyhedral cells, different SGS models?? Conclusions and future work • Acknowledgements: • UK research council project “Keeping the Nuclear Option Open” (KNOO)

More Related