Velocity inertial subrange model: Difference between revisions

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= 1.5 <ref name="Sreenivasan">{{Cite journal
= 1.5 <ref name="Sreenivasan">{{Cite journal
|authors= K. R. Sreenivasan
|authors= K. R. Sreenivasan
|journal= Phys. Fluids
|journal_or_publisher= Phys. Fluids
|papertitle=  On the universality of the Kolmogorov constant
|paper_or_booktitle=  On the universality of the Kolmogorov constant
|year= 1991
|year= 1995
|doi= 10.1063/1.868656
|doi= 10.1063/1.868656
}}</ref>. Amongst the three direction, the spectra deviates by the constant <math>a_j</math>:
}}</ref>. Amongst the three direction, the spectra deviates by the constant <math>a_j</math>
<ref name="Pope">{{Cite journal
|authors= S.B Pope
|journal_or_publisher= Cambridge Univ. Press
|paper_or_booktitle=  Turbulent flows
|year= 2000
|doi= 10.1017/CBO9780511840531
}}</ref>
:
* In the longitudinal direction, i.e., the direction of mean advection (j=1), <math>a_1=\frac{18}{55}</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>  
* In the other directions <math>a_2=a_3=\frac{4}{3}a_1</math>  

Revision as of 19:52, 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_{Vj}(\hat{k})=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]. [math]\displaystyle{ C_k }[/math] is the empirical Kolmogorov universal constant of C = 1.5 [1]. Amongst the three direction, the spectra deviates by the constant [math]\displaystyle{ a_j }[/math] [2]

  • 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

Notes

  1. K. R. Sreenivasan. 1995. On the universality of the Kolmogorov constant. Phys. Fluids. doi:10.1063/1.868656
  2. S.B Pope. 2000. Turbulent flows. Cambridge Univ. Press. doi:10.1017/CBO9780511840531