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July 5, 2019, 07:59 
Energy spectrum in frequency

#1 
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Ashish bhigah
Join Date: Jan 2019
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Hi I am trying to calculate the Energy spectrum, which is a concept usually applied to the wavenumber, but I want to calculate an energy spectrum in frequency.
In order to do that I calculated the autocorrelation function of 3 component of velocity in one point. I did the psd of the 3 component using the autocorrelation function not normalised. Then I summed them and I divided these by two. So It is respected the fact that the mean value of turbulent kinetic energy is equal to the integral of the energy spectrum over the frequency. do you think that this approach can be acceptable in order to calculate the energy spectrum in frequency? 

July 5, 2019, 08:27 

#2  
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Filippo Maria Denaro
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Quote:
frequency and wavenumber is almost the same since k=n*2*pi/L 

July 5, 2019, 08:33 

#3 
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Ashish bhigah
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Yes, it is what I was thinking. So this approach can be acceptable?


July 7, 2019, 07:58 

#4 
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Emma
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July 7, 2019, 10:54 

#5 
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Ashish bhigah
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Tags 
energy spectrum, frequency 
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