ME-716 / 2 crédits

Enseignant: Ancey Christophe

Langue: Anglais

Remark: Next time: Fall 2026


Frequency

Every 2 years

Summary

The course is an introduction to symmetry analysis in fluid mechanics. The student will learn how to find similarity and travelling-wave solutions to partial differential equations used in fluid and continuum mechanics. The course covers mathematical and physical aspects

Content

Chapter 1: The concept of similarity

•          Geometrical similarity

•          Invariance by affine transformation, rotation, translation

•          Fractal similarity

•          Scaling law

•          Physical similarity

•          Complete similarity: drag force

•          Incomplete similarity: flow resistance

Chapter 2:  Transport phenomena in fluid dynamics

•          Transport phenomena

•          Advection

•          Diffusion Heat equation

•          Wave

•          Shocks and conservation equations

•          Boundary problems: fixed boundary, boundary layer, free boundary problem

•          Classification of partial differential equations

•          First-order equation, characteristic form

•          Second order equation, hyperbolic, elliptic, parabolic

Chapter 3: One-parameter groups, Lie groups

•          Groups of transformation

•          Group invariants

•          Invariant curves

•          Transformation of derivative

Chapter 4: First-order differential equations

•          Phase portrait

•          Singular point

•          Separatrix

•          Integrating factor

•          Invariant integral curves

•          Singular solution

•          Change of variables

Chapter 5: Second-order differential equations

•          Invariant differential equations

•          Lie’s reduction theorem

•          Stretching group

•          Singularities

Chapter 6: Similarity solutions to partial differential equation

•          Similarity solutions

•          Associated stretching group

•          Asymptotic behavior

•          Determining equations

Chapter 5: Travelling wave solution

•          Translation groups

•          Example: diffusion with source

•          Propagation velocity

•          Approach to travelling waves

Chapter 8: Hyperbolic problems

  Hyperbolic problems

•          One dimensional problems

•             Characteristic equations

•             Shock formation

•            The Riemann problem

  Generalization to multidimensional problems

•             Linear systems

•             Nonlinear systems

•            The shallow-water equations

Chapter 9: Parabolic problems

•          Linear diffusion

•          Nonlinear diffusion

•          Stefan problem

•          Boundary layer problem

Keywords

partial differential equation, diffusion, advection, similarity solutions, travelling wave solution, hyperbolic problems

Resources

Bibliography

Bibliography is provided on the webpage

Websites

Moodle Link

Dans les plans d'études

  • Nombre de places: 20
  • Matière examinée: Similarity and Transport Phenomena in Fluid
  • Cours: 20 Heure(s)
  • Exercices: 8 Heure(s)
  • Type: optionnel

Semaine de référence

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