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Turbomachinery flow LES computation using high order method


Required Education : Thèse de doctorat / PhD Thesis
Start date : 1 June 2015
Mission duration : 1 an
Salary : 2300/mois

Required Education / Niveau requis

PhD thesis

From / Date de début

October 2015

Duration / Durée

1 year

Context / Contexte

The CFD team develops and maintains the most advanced codes for fluid mechanics dedicated to industrial problems. We currently work with ONERA, Airbus, SAFRAN (Snecma / Turbomeca) and EDF.

Maintaining our expertise on CFD needs to propose new solutions or to adapt solutions published in the literature to industrial meshes / configurations. It is clear that turbulence-averaged simulations (RANS and URANS approaches) with second-order schemes are dedicated to design but they are not well adapted to compute off-design configurations. Off-design configurations need unsteady computations and high order (spatial and temporal) schemes to propagate flow physics inside the computational domain. Aeroacoustic, vortex-dominated flow and some turbulence-driven phenomena are examples of application of high order schemes.

Description / Description

We are currently developing a new solver called JAGUAR. JAGUAR solves the Navier-Stokes equations in their strong form, following the Spectral Difference paradigm. The Spectral Difference approach is based on a high order polynomial representation of variables inside each mesh cells and does not impose continuity at cell interfaces. In many aspects, it looks like the famous Discontinuous Galerkin technique but it shares many aspects with Finite Differences while Discontinuous Galerkin is based on Finite Element. Its order of accuracy is chosen between 1 and 10. Many aspects related to JAGUAR, its efficiency and the Spectral Difference method are available on http://www.cerfacs.fr/~puigt/jaguar.html. JAGUAR is designed to perform massively parallel Euler, Navier-Stokes and (implicit) Large Eddy Simulations with efficiency and it includes OpenMP, MPI, hybrid OpenMP/MPI and GPGPU treatments.

Up to now, JAGUAR has been mainly applied on standard academic configurations to analyse both the code efficiency and its accuracy (convection of an isentropic vortex, LES of channel flow, Taylor Green Vortex…). Now, the goal is to go further in the analysis, using the CFD code for LES of turbomachinery. The post-doc position deals with the extension of JAGUAR to turbomachinery application and it is proposed inside a project founded by one of our shareholders. Several points must be addressed:

Implementation of curved boundary
LES simulation around a single blade, comparison with solutions ever obtained with AVBP and elsA
Implementation of dedicated boundary conditions (inflow and outflow)
Mesh generation and computations.
For this position, we look for a someone who

Desires to work in a team
Has a good knowledge in Fortran and in programming
Has a basic knowledge in numerical schemes for convection, especially in classical 1D schemes
Has knowledge in LES ingredients, including standard boundary conditions (Poinsot & Lele's NSCBC…)
Takes initiative

Contacts / Contacts

Name: Puigt Guillaume

Phone: +33 (0)5 61 19 30 94
Fax: +33 (0)5 61 19 30 00
Email: guillaume.puigt@cerfacs.fr

Name: Boussuge Jean-François
Phone: +33 (0)5 61 19 30 62
Fax: +33 (0)5 61 19 30 00
Email: boussuge@cerfacs.fr

Salary / Rémunération

About 2 300 euros / month