Structure function empirical constant

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Short definition of Structure function empirical constant (<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): Used Doppler radar measurements of turbulence in the atmosphere to obtain a value of <math>2.0\pm 0.1</math>
  2. Saddoughi and Veeravalli (1994): Used measurements in a wind tunnel to obtain a value of <math>2.1\pm 0.1</math>
  3. Sreenivasan (1995): 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