What is VBT theory



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Table of Contents



  1. introduction
    1. General characterization of turbulence
    2. Features of turbulent flows
    3. Turbulence generation, turbulence categories
    4. Turbulent currents in nature and technology
  2. Basics in the field of laminar flows
    1. Field-local flow field kinematics / deformation and rotation tensor
      1. Representation of the local kinematic state in Cartesian coordinates
      2. Rotation and deformation tensor from the decomposition of the tensor of the local state of relative motion
      3. Field-local kinematic state as a superposition of translation, rotation and deformation
      4. Volume dilation and divergence
    2. Flow field differential equations from mass and momentum balances
      1. Mass balance / continuity equation
      2. Momentum balance equation, frictional stresses
    3. Energy analysis of laminar, incompressible flows / energy dissipation
    4. Flow field equations of energy and mass transport
      1. Transport equation for thermal energy
      2. Transport equation for substance species
    5. Laminar and turbulent flows / Reynolds number as a discrimination parameter
  3. Turbulent impulse, heat and mass transport
    1. Decomposition of turbulent flow quantities into mean values ​​and fluctuation values
    2. Turbulent momentum and scalar exchange
    3. Gradient approaches for turbulent-diffusive transport quantities / transport flow densities
    4. Reynolds equations
      1. Reynolds decomposition of turbulent field quantities
      2. Reynolds’s equations of flow for incompressibility
      3. Turbulent scalar transport equation for incompressibility
    5. Reynolds number dependence of the turbulent, incompressible, time-averaged transport equations
    6. Turbulent transport equations for flow fields of varying density using Favre averaging
      1. Favre averaging and Favre fluctuation components / definition
      2. Favre decomposition applied to mass flux terms / continuity equation
      3. Favre decomposition applied to momentum current density terms / momentum balance equation
      4. Favre decomposition applied to the scalar transport terms and the scalar transport equation
    7. Mode of action of
    8. Analogy between molecular and fluidic viscosity
    9. Molecular toughness (internal friction)
    10. Prandtl’s mixing path approach
  4. Dynamics of turbulence
    1. Equation of the kinetic energy of the main flow
    2. Equation of the kinetic energy of the turbulent oscillatory motion
    3. Equation for the vortex strength (vortex transport equation)
    4. Reynolds equation for turbulent flow layers
      1. Current near solid walls
  5. The energy cascade
  6. Premix flames
    1. Laminar flame propagation - thermal theory
    2. Turbulent premix combustion
      1. Parameters and key figures of the Borghi diagram
      2. Mathematical flame model for premixed flames according to Hans-Peter Schmid



The script will be handed out to accompany the lecture.



application areas

The lecture material is the basis of many scientific and industrial applications, especially in the field of gas turbines and internal combustion engines.