Work done:
o Management of the simulation team based in China, Europe and Mécanique
o Thermal
o Rhéology
- Thermal Simulation of the ligthing system for the clients (VW, Renault-Nissan, Pegeot-Citroen, Volvo..)
- Laboratories tests
o Durability
o Yellowing
o Mechanic
o Radiation
- Valeo validation system (V cycle)

Results achieved:
- Writing a technical note
- Presentation for the costumer

Work done: (to detail)
- Fortran development using the IAST methodology
- Validation with experimental data
- Meeting with the costumer (Agile process)

Results achieved:
- Writing a technical report
- Presentation to the costumer

Work done:
- Bibliography
o Hydrogen problem
o Passive condensors /PCCS
o The filters(Collaborations with many suppliers)
o Mixing gas
o Catalytic recombinor
- VBA development of the thermal properties of the mixing gas (using a NASA-USA publication)
- Modelling a recombinor using Ansys WorkBench
- Thermal simulation using Ansys-Mechanical

Results achieved:
- Writing a technical report
- Presentation to the costumer
- Collaboration with many actors of the french nuclear
o IRSN
o AREVA
o EDF

Work done:
- Numerical Modelling of the nuclear plant using code CATHAR 2
o Coupling CATHAR 2 / Validation with the experiment data and the correlations
Results achieved:
- Writing a technical report
- Presentation to the costumer

Work done:

- Meshing
o Cooling system
o The whole reactor
- Pre-Processing
o Boundaries conditions
o Spatial Numerical scheme discretization
o Temporal Numerical scheme discretization
o Steady state and transient simulations
o Turbulent model
• RANS (k-epsilon)
o Radiation model
 Monte Carlo
 P1
 DTM
 DO
o Multi processor calculation (MPI)
- Process with Ansys CFX
- Post-processing with Ansys CFX

Results achieved:
- Writing a technical note
- Wrinting and article in the journal Nuclear and Engineering

Abstract
Thermal fatigue in Pressurized Water Reactor plants has been found to be very acute in some hot/cold Tee junction mixing zones. Large Eddy Simulation (LES) can be used to capture the unsteadiness which is responsible for the large mechanical stresses associated with thermal fatigue. Here one LES subgrid model is studied, namely the Dynamic Smagorinsky model. This paper has two goals. The first is to demonstrate some results obtained using the EDF R&D Code Saturne applied to the Vattenfall Tee junction benchmark (version 2006) and the second is to look at the effect of including synthetic turbulence at the Tee junction pipe inlets. The last goal is the main topic of this paper. The Synthetic Eddy Method is used to create the turbulent inlet conditions and is applied to two kinds of grids. One contains six million cells and the other ten million. The addition of turbulence at the inlet does not seem to have much effect on the bulk flow and all computations are in good agreement with the experimental data. However, the inlet turbulence does have an effect on the near wall flow. All cases show that the wall temperature fluctuation and the wall temperature/velocity correlation are not the same when a turbulent inlet condition is used. Inclusion of the turbulent inlet condition moves the downstream location of the maximum temperature/velocity correlation by 1 cm and reduces its magnitude by 10%. This result is very important because the temperature/velocity correlation is closely related to the turbulent heat transfer in the flow, which is in turn responsible for the mechanical stresses on the structure. Finally we have studied in detail the influence of the turbulent inlet condition just downstream of the mixing zone. We show the influence of including turbulent inlet condition on the structure of the flow Walker et al. (2009).
Highlights
► LES of Tee junctions can easily reproduce the bulk flow. ► The presence or absence of a turbulent inlet condition has an affect on the wall heat transfer. ► The maximum heat transfer moves 1 cm and reduces by 10% when a turbulent inlet is used.

Work done
- Meshing
o Mixing Tee
- Pre-Processing
o Boundaries conditions
o Spatial Numerical scheme discretization
o Temporal Numerical scheme discretization
o Steady state and transient simulations
o Turbulent models
• RANS (k-epsilon, K-Omega)
• LES (Large Eddy Simulation)
o Smagorinsky
o Gueurt
o Radiation model
 DO
- Parralle simulation (MPI)
o Blue Gene P et Q
o CCRT (CEA)
o Ivanoe
- Simulation Type
o RANS
o LES
o DNS
- Process and solver Code-Saturne
- Post-processing Ensight

Results achieved:
- Writting a thesis report.
- Writting an articlein the international journal NED (Nuclear Engineering and Design)
- Presentation in fort of the revievers

Publications

o Ndombo JM . Numerical modelling of an isothermal flow in a mixing Tee using large eddy simulation (http://www.theses.fr/2013AIXM4370)
o NNdombo J.-M, Howard R.J.A and Serre E. Thermal Heat Flux Analysis at the Wall of a Mixing Tee (abstract). Turbulent Heat and Mass Transfer, 2012, Italy.
o NNdombo J.-M, Howard R.J.A and Serre E. Turbulent Statistics in a Mixing Tee Junction, Proceeding of Engineering Turbulence Mechanic and Measurement 9, 2012 Greece.
o Ndombo J.-M and Howard R.J.A. Large Eddy Simulation and the effect of the turbulent inlet conditions in the mixing Tee. Nuclear Engineering and Design Vol 241 (2011) 2172-2183
o NNdombo J.-M. Poster and T-junction benchmark OECD/NEA CFD for nuclear Reactor safety, 2010 Washington (USA).
o MMultiscale analisis of heat transfer in coated fuel particle compacts-Application to the HTTR. X. Garnaud X. Han JM Ndombo I. Limaiem
o NNdombo J.-M et al. Thermal Hydraulic and Neutronic coupling of the HTTR (in progress)