Numerical methods for Large Eddy Simulation
nasri | Training
Announced
Deadline for registration: 15 days before the starting date of each training
Duration : 5 days / (35 hours)
Abstract
This training session allows participants to understand the underlying basics of Large Eddy Simulation (LES): numerics, boundary conditions, LES closures and combustion modeling. The CFD code AVBP (version 7.0.2) co-developed by CERFACS and IFPEN is used for hands-on to compute both academic and realistic configurations of reacting compressible flows.
Target participants
This training session is for engineers, physicists, computer scientists and numerical analysts who wish to learn to use LES and to manipulate a CFD code dedicated to LES.
Prerequisites
Unix, Fortran, numerical simulation.
Scientific contact : Eleonore RIBER
Fee
- Trainees/PhDs/PostDocs : 350 €
- CERFACS shareholders/CNRS/INRIA : 1000 €
- Public : 2000 €
Program
(Every day from 9h to 17h30)
Day 1 – Introduction / numeric for LES
9h00 Welcome and coffee
9h15 LES of reacting compressible flows – Introduction
The differences between RANS and LES.
The codes for LES.
10h45 How does AVBP work
Files – scripts – general organization.
11h30 Installation on computers – accounts – computer organization
14h00 Numerical schemes needed for LES. Dissipation and dispersion of waves. Implementation of numerical schemes in AVBP
15h00 Hands-on work on computers: measurement of dispersion and dissipation, effect of mesh and scheme for two canonical cases: the convection of two-dimensional vortices and the shear layer
Day 2 – Bounday conditions
9h00 Boundary conditions in compressible flows: characteristic methods
9h45 Implementation of boundary conditions in AVBP
10h30 Hands-on: simulation of one-dimensional acoustic waves reaching non-reflecting boundaries
Generation of propagating acoustic waves.
14h00 Hands-on: manipulation of boundary conditions to mimic reflexions or to produce non-reflecting conditions
Applications to vortices going through outlet.
Day 3 – LES of gaseous turbulent reacting flows
9h00 LES of reacting flows: thermodynamics, kinetics, laminar flames and turbulent combustion model, closure models for LES and wall modelling
10h30 Hands-on: post-processing LES of turbulent flow. Effect of subgrid-scale model, wall model and grid refinement
14h00 Hands-on: simulation of one-dimensional laminar flame (initial flame file (CANTERA) is provided) with and without flame thickening
16h00 Hands-on: simulation of a forced two-dimensional laminar flame
Day 4 – LES of two-phase flow turbulent reacting flows
9h00 LES of two-phase reacting flows: Euler-Euler (EE) and Euler-Lagrange (EL approaches, evaporation, injection, liquid-wall interactions, two-phase combustion mode
10h30 Hands-on: simulation of two-phase canonical cases using both EE and EL approaches
14h00 Hands-on: simulation of a one-dimensional two-phase laminar flame
16h00 Hands-on: LES of an heptane air swirled combustor
Day 5 – Deatailed analysis of LES – spot the difference
9h00 Hands-on: spot the difference on a three-dimensional LES deliberately ridded with errors
14h00 Custom made afternoon: participants are welcome to discuss about their current objectives/perspectives/problems using AVBP with the senior researchers of the CFD team