Interaction between periodic wake passing and boundary-layer transition in a low-pressure turbine using LES
Required Education : PhD degree
Mission duration : 12 months
Salary : 2400 euros/month
We have an opening for a one-year postdoc position (eventually renewable), to focus on rotor wake – stator boundary layer interaction using Large-Eddy Simulations.
This project consists in studying the impact of a periodic rotor wake passage on a stator boundary layer transition to turbulence. This boundary layer transition to turbulence is a complex phenomenon, highly dependant on the upstream conditions, which is likely to modify the entire flow topology. It induces aerodynamic losses, and finally impacts the overall engine efficiency.
Current computational resources allow Large Eddy Simulation (LES) to be used as an investigation tool in turbomachinery configurations. A significant attention must however be paid to the numerical methodologies and the mesh quality when focusing on such a complex and sensitive physics.
The project first aims at assessing LES predictions in an academic cascade configuration, where periodic wake passing is generated with moving bars located upstream of the cascade. The numerical solver under consideration is AVBP, an unstructured and massively parallel LES solver, which has demonstrated its ability to simulate rotor-stator configurations and challenging configurations.
Numerous experimental measurements have been performed at the Von Karman Institute on an academic configuration representative of a Low Pressure Turbine, at high Mach number and rather low Reynolds number. These average and turbulent flows measurements will allow numerical predictions/experimental comparisons.
Once numerical simulations would have been validated at nominal regime, in-depth physics investigation will be conducted, and the effect of regime and wake passing frequency will be studied.
The candidate should hold a PhD degree in mechanical engineering, aeronautics, fluid mechanics or any related field. He/she would have experience/knowledge in turbomachinery flow physics, Large-Eddy Simulations, High-Performance Computing, turbulence. Experience with programing (Python, Fortran) and numerical methods is a major plus.
The candidate is expected to be self-motivated, willing to learn the considered LES solver, to conduct research and communicate results in conferences and journals.
In practise/ Contact:
The project is funded by Safran Aircraft Engines, the position will be held at CERFACS (Toulouse, France). The candidate will work within a dynamic team of PhDs and postdocs, with high academic potential and strong relations with industrial partners.
Net salary: around 2400 euros/month.
Expected beginning: September/October 2019
Send CV and cover letter + name of 2 references contacts.
Nicolas Odier / firstname.lastname@example.org
Jérôme Dombard / email@example.com
Laurent Gicquel / firstname.lastname@example.org
Florent Duchaine / email@example.com