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Old   February 26, 2006, 04:40
Default RMS velocity
  #1
user
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hello everybody

Is it possible to get the value Root mean Square(RMS ) velocity of fluid in CFX post

please help me

with regards user

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Old   February 26, 2006, 04:54
Default Re: RMS velocity
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TB
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Are you talking about steady- or transient-flow? Try giving a bit more details here...
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Old   February 26, 2006, 09:26
Default Re: RMS velocity
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hello thanks for replying i am talking abt transient flow i want to get the value of the normal and shear stress, for that i am trying to get root mean squre velocity

with regards user
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Old   February 27, 2006, 13:37
Default Re: RMS velocity
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Robin
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Just enter an expression for the root mean square. For any variable, say Phi

RMS Phi = sqrt(sum(Phi^2))

Simple.
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Old   February 27, 2006, 20:52
Default Re: RMS velocity
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Eike
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Hi An other way to get the RMS is to include a transient statistic. You can do this on the output control panel. regards eike
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Old   February 27, 2006, 23:15
Default Re: RMS velocity
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Robin
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Sorry, missed the fact that this was transient. Disregard my suggestion. Eike has the right idea.

-Robin
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Old   February 27, 2006, 23:54
Default Re: RMS velocity
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TB
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Eike is right. If you have already run the solver, consider output the variable vs time and calculate rms value manually in Excel or Matlab or any other software that may suit you. You can also write a small program using command window if you know how.
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Old   February 28, 2006, 04:19
Default Re: RMS velocity
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user
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hello Robin,Elike and TB

thanks for taking more effort let me know how do i include RMS in output control panel i thing i have to include the Root mean square option in trantient statics is it correct or not

please help me

user
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