Time averaging a product of fluctuations <u'T'>
 

Hi everyone,

I would like to calculate turbulent heat fluxes, which are defined as the time averages of the velocity and temperature fluctuations:

<u' T'> where <..> denotes a time averaging operation, and u' and T' are respectively the velocity and temperature fluctuations.

Is there an easy solution to achieve this? I tried with the fieldAverage function in the controlDict but there it is only possible to calculate the prime-squared mean values of 1 field, e.g. <u'u'>. Someone has a solution?

Kind regards,
Laurien

You can try to create a field U*T somehow, then <u'T'>=<UT>-<U><T>, where I assume you are tracking the mean quantities anyhow.

Hi, Laurien!

Have you found a solution yet? I want to calculate <u' T'> too. It would be very kind of you to share some information about this problem.

Best regards,
Peter

Hello

were you able to find a solution for this? I am wondering I have to modify the fieldAverage function, but it's not so easy to understand the code...