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Vaulter March 10, 2010 07:16

Wind turbulence measurement
 
Hi,
How can one measure wind turbulence in PHOENICS.
I add up (stored of TINT is KE^0.5/VABS with IMAT<100) in IN FORM7 for turbulence intensity but I don't know what it means and how its working. Its output results are also very suspicious.

Linh.Hoang March 10, 2010 08:58

Hi Vaulter,
to calculate the turbulence intensity you just need KE.
For isotropic turbulence: KE=0.5*(u'**2+v'**2+w'**2) = 0.5*(3 u'**2).
the turbulence Intensity: I=u'/Vabs= SQRT(3/2*KE)/Vabs.

(stored of TINT is KE^0.5/VABS with IMAT<100)
means that you store a new variable named TINT and that TINT= SQRT(KE)/Vabs
Im not quite sure why you choose this formula i would recommend the one i mentioned above.


If you want to model the Wind just try the Wind Object (see POLIS)


Linh

Vaulter March 10, 2010 10:49

Quote:

Originally Posted by Linh.Hoang (Post 249349)
Hi Vaulter,
to calculate the turbulence intensity you just need KE.
For isotropic turbulence: KE=0.5*(u'**2+v'**2+w'**2) = 0.5*(3 u'**2).
the turbulence Intensity: I=u'/Vabs= SQRT(3/2*KE)/Vabs.

(stored of TINT is KE^0.5/VABS with IMAT<100)
means that you store a new variable named TINT and that TINT= SQRT(KE)/Vabs
Im not quite sure why you choose this formula i would recommend the one i mentioned above.


If you want to model the Wind just try the Wind Object (see POLIS)


Linh

Thanks Linh I will check it out...


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