Velocity inertial subrange model: Difference between revisions

From Atomix
Line 6: Line 6:
== Inertial subrange for steady-flows ==
== Inertial subrange for steady-flows ==
This theoretical model predicts the spectral shape of velocities in wavenumber space.  
This theoretical model predicts the spectral shape of velocities in wavenumber space.  
<math>\Psi(\hat{k})_{Vj}=a_jC_k\varepsilon^{2/3}\hat{k}^{-5/3}</math>
<math>\Psi(\hat{k})_{Vj}=a_jC_k\varepsilon^{2/3}\hat{k}^{-5/3}</math>
Here <math>\hat{k}</math> is expressed in rad/m and <math>Vj</math> represents the velocities <math>V</math>  in direction <math>j</math>. Amongst the three direction, the spectra deviates by the constant <math>a_j</math>:
* In the longitudinal direction, i.e., the direction of mean advection (j=1), <math>a_1=\frac{18}{55}</math>
* In the other directions <math>a_2=a_3=\frac{4}{3}a_1</math>


[[File:InertialSubrange.png]]
[[File:InertialSubrange.png]]

Revision as of 18:55, 11 November 2021


Short definition of Velocity inertial subrange model
The inertial subrange separates the energy-containing production range from the viscous dissipation range.

This is the common definition for Velocity inertial subrange model, but other definitions maybe discussed within the wiki.

Inertial subrange for steady-flows

This theoretical model predicts the spectral shape of velocities in wavenumber space.

[math]\displaystyle{ \Psi(\hat{k})_{Vj}=a_jC_k\varepsilon^{2/3}\hat{k}^{-5/3} }[/math]

Here [math]\displaystyle{ \hat{k} }[/math] is expressed in rad/m and [math]\displaystyle{ Vj }[/math] represents the velocities [math]\displaystyle{ V }[/math] in direction [math]\displaystyle{ j }[/math]. Amongst the three direction, the spectra deviates by the constant [math]\displaystyle{ a_j }[/math]:

  • In the longitudinal direction, i.e., the direction of mean advection (j=1), [math]\displaystyle{ a_1=\frac{18}{55} }[/math]
  • In the other directions [math]\displaystyle{ a_2=a_3=\frac{4}{3}a_1 }[/math]

Inertial subrange for flows influenced by surface waves

Need to add equations and figures from Lumley & Terray