Numerical methods for Large Eddy Simulations
From Monday 26 November 2018 to Friday 30 November 2018
Training
Announced
Deadline for registration: 15 days before the starting date of each training
Duration : 5 days / (35 hours)
Abstract
This training course allows participants to understand the underlying basics of two-phase reacting Large Eddy Simulation (LES): numerics, boundary conditions, LES closures, two-phase flow and combustion modeling. The version 7.0.2 of AVBP has been used for hands-on since October 2016 to compute both academic and realistic configurations of two-phase 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
Fee
Trainees/PhDs/PostDocs : 300 €
CERFACS shareholders/CNRS/INRIA : 900 €
Public : 1800 €
Program
(Every day from 9h to 17h30)
Day 1:Introduction / Numeric for LES
9:00 Welcome and coffee
9:15 LES of reacting compressible flows – Introduction. The differences between RANS and LES. The codes for Large Eddy Simulation
10:45 How does AVBP work: files – scripts – general organization / Installation on computers, accounts, computer organization
11:30 How does Paraview work
14:00 Numerical schemes needed for LES. Dissipation and dispersion of waves. Implementation of numerical schemes in AVBP
15:00 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 instability growth of a linear shear layer
Day 2: Boundary conditions
9:00 Boundary conditions in compressible flows: characteristic methods
9:45 Implementations of boundary conditions in AVBP
10:30 Hands-on: simulation of one-dimensional acoustic waves reaching non-reflecting boundaries. Generation of propagating acoustic waves
14:00 Hands-on: manipulation of boundary conditions to mimic reflections or to produce non-reflecting conditions. Application to two-dimensional vortices going through outlet
15:30 Hands-on: manipulation of boundary conditions to deal with walls and corners. Application to two-dimensional straight channel with sudden expansion
Day 3: LES of gaseous turbulent reacting flows
9:00 LES of reacting flows: thermodynamics, kinetics, laminar flames, turbulent combustion model, closure models for LES and wall modelling
10:30 Hands-on: post-processing LES of turbulent pipe flow. Effect of subgrid-scale model, wall model and grid refinement
14:00 Hands-on: simulation of a one-dimensional laminar flame (initial flame file (CANTERA) is provided) with and without flame thickening
16:00 Hands-on: post-processing the LES of a turbulent gaseous swirled propane-air flame
Day 4: LES of two-phase turbulent reacting flows
9:00 LES of two-phase reacting flows: Euler-Euler (EE) and Euler-Lagrange (EL) approaches, evaporation, injection, liquid-wall interactions, two-phase combustion modes
10:30 Hands-on: simulation of two-phase canonical cases using both EE and EL approaches
14:00 Hands-on: simulation of a one-dimensional two-phase laminar flame
16:00 Hands-on: LES of a n-heptane-air swirled combustor
Day 5: Detailed analysis of LES – spot the difference
9:00 Hands-on: spot the difference on a three-dimensional LES deliberately riddled with errors
14:00 Custom-made afternoon : participants are welcome to discuss about their current objectives/perspecti- ves/problems using AVBP with the senior researchers of the CFD team
