Structure function empirical constant

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(<math>C_2</math>)| }}
The empirical constant relating the longitudinal structure function <math>D_{LL}</math> to the dissipation rate (<math>\varepsilon</math>)

This is the common definition for Structure function empirical constant, but other definitions maybe discussed within the wiki.

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Dimensional analysis can be used to show that <math>D_{LL}</math> must satisfy the "two-thirds law", i.e., <math>D_{LL}(r,t) = C_2\varepsilon^{2/3}r^{2/3}</math> where <math>C_2</math> is a universal constant.

The value of the constant is generally accepted to be <math>2.1\pm 0.1</math>, based on the following studies:

  1. Sauvageot (1992)<ref name="Sauvageot">

{{#arraymap:H. Sauvageot|,|x|x|, |and}}. 1992. Radar Meteorology. Artech House. doi:{{{doi}}} </ref>: Used Doppler radar measurements of turbulence in the atmosphere to obtain a value of <math>2.0\pm 0.1</math>

  1. Saddoughi and Veeravalli (1994)<ref name="Saddoughi">

{{#arraymap:K. R. Sreenivasan|,|x|x|, |and}}. 1994. Local isotropy in turbulent boundary layers at high Reynolds number. J. Fluid Mech.. doi:https://doi.org/10.1017/S0022112094001370 </ref>: Used measurements in a wind tunnel to obtain a value of <math>2.1\pm 0.1</math>

  1. Sreenivasan (1995) <ref name="Sreenivasan">

{{#arraymap:K. R. Sreenivasan|,|x|x|, |and}}. 1995. On the universality of the Kolmogorov constant. Phys. Fluids. doi:10.1063/1.868656 </ref>: Compiled the results from experimental studies of both grid turbulence and shear flows to conclude that a value of 2.0 agreed best with the spectral inertial subrange equation

Notes