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Hi All,

What is the proper way to specify a noise force and a body force at the same time?

I am new to Nektar++, and am attempting to run a simulation of turbulent channel flow using a body force to drive the bulk flow, and a noise force to generate some initial "turbulent-like" fluctuations of the velocity field.  However, when I setup the case based on the details found in the user guide (Forcing (nektar.info) ), the resulting flow field doesn't show any "noise component".  Is there some error in my settings for this case?:

<NEKTAR>
   <CONDITIONS>
      ...
     <FUNCTION NAME="BodyForce">
             <E VAR="u" VALUE="-(Re*Kinvis/H)^2/H" />
             <E VAR="v" VALUE="0" />
             <E VAR="w" VALUE="0" />
         </FUNCTION>

     </CONDITIONS>
     <FORCING>
         <FORCE TYPE="Body">
             <BODYFORCE> BodyForce </BODYFORCE>
         </FORCE>
         <FORCE TYPE="Noise">
             <WHITENOISE> 0.5 </WHITENOISE>
             <UPDATEFREQ> 10 </UPDATEFREQ>
         </FORCE>
     </FORCING>
 </NEKTAR>

Regards,

Marc Goldbach
PhD Student, Department of Mechanical Engineering
University of North Carolina at Charlotte