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The 4 May 2020

Implementation and use of Lattice Boltzmann Method

nasri |  

Postponed
Deadline for registration: 15 days before the starting date of each training
Duration : 1 day / (6 hours)

Pre-registration

Abstract

The approach called Lattice Boltzmann Method (LBM) is based on the resolution of the Boltzmann equation and not the Navier-Stokes ones (to notice: Navier-Stokes is an approximation of Boltzmann). LBM is based on gas kinetics theory; to obtain the macroscopic behavior of the fluid we work on a smaller physical scale (called mesoscopic) compared to conventional approaches.

This paradigm shift has several advantages. Boltzmann equations are simpler than the Navier-Stokes equations, this means a more compact solver, easier to write and maintain. Moreover arithmetic operations to be performed are local, this implies a high efficiency on parallel computers. But what makes this approach very promising for the future is its ability to handle very complex geometries without any difficulty.

Objective of the training

This training aims to provide basic knowledge in the implementation of an LBM solver.

Learning outcomes

On completion of this training course, you will be able to :

  • Understand the different algorithms present in a basic LBM code,
  • Implement these algorithms in a simplified platform,
  • Set up and simulate academic test cases not provided in the training.

Target participants

This training session is for engineers, physicists, computer scientists and numerical analysts who want to start learning LBM.

Prerequisites

In order to follow this course, you need to:

  • Knowledge of Unix commands.
  • Basic knowledge of C programming.
  • Knowledge of numerical flow simulations.

In order to verify that the prerequisites are satisfied, the following questionnaires must be completed. You need to get at least 75% of correct answers in order to be authorized to follow this training session. If you don’t succeed it, your subscription will not be validated. You only have two chances to complete it.

Questionnaire 1 : https://goo.gl/forms/0pVpY56riihNUG6V2

Questionnaire 2 : https://goo.gl/forms/CNVWTQkIQJXaxsTo2

Scientific contact

Jean-François BOUSSUGE

Fee

  • Trainees/PhDs/PostDocs : 70 €
  • CERFACS shareholders/CNRS/INRIA : 200 €
  • Public : 400 €

Program

  • Conceptual understanding of LBM
  • Derivation of the LBM equation
  • Numerical aspects of the LBM equation (stream and collide approach)
  • Implementation
    Collision operator
    Streaming operator
    Simple boundary condition
    Bounce back
    Periodic
  • Incorporate a forcing term
    Practical work
  • Study of a simple LBM solver
  • Application to academic test cases
    Poiseuille flow
    Couette flow
    Flow past a cylinder
    Lid driven cavity
    Double shear layer

Final examination

A final exam will be conducted during the training.

Pre-registration

 

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