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August 18, 2009, 07:34 
Volume Fraction, profile data problem

#1 
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Hi,
I´m simulating waves using profile data at the inlet. As I have experimental data from the height of the wave vs time, I used a profile data containing x,y,z and volume fraction as columnes. The results aren´t correct. x and y are fixed values (the point where the height of the wave is measured). I have put x as the time and y = 0 all time. z is the mesured height. Volume Fraction values are 1 or 0 depending on the value of z (positive or negative) The expression: Filename.Volume Fraction((t*1[s^1]*1[m]),y,z) It doesn´t work!!! Would kindly anyone tell me what could be wrong? Thank you very much in advance Cfxmar 

August 18, 2009, 18:25 

#2 
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Glenn Horrocks
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I think a 1D interpolation function would be more appropriate than the 3D one you are using. Try that.
Glenn Horrocks 

August 19, 2009, 04:39 

#3 
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Thank you, Glenn.
I have tried that but as the problem is 3D, the profile data needs three columns for x,y,z and one for the volume fraction. CFX doesn´t let me load the profile data file with only 2 columns (one for x as the time and one for the volune fraction) 

August 19, 2009, 04:47 

#4 
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Lance
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I just did the same thing, but for a measured mass flow rate instead and a 1D profile data function worked fine for me.
Looks like: FUNCTION: MassFlowInlet Argument Units = [m] Extend Max = true Extend Min = true File Name = massflow.csv Option = Profile Data Spatial Fields = X DATA FIELD: Mass Flow Rate Field Name = Mass Flow Rate Result Units = [kg s^1] END END and the boundary condition: BOUNDARY: inlet Boundary Type = INLET Location = F18.16 BOUNDARY CONDITIONS: FLOW DIRECTION: Option = Normal to Boundary Condition END FLOW REGIME: Option = Subsonic END MASS AND MOMENTUM: Mass Flow Rate = MassFlowInlet.Mass Flow Rate(FT) Option = Mass Flow Rate END TURBULENCE: Option = Low Intensity and Eddy Viscosity Ratio END END END where FT is defined as FT = 1[m/s]*t Lance 

August 19, 2009, 05:45 

#5 
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Thank you very much, Glenn and Lance.
I´m running the simulation, tomorrow I will see the results. Cfxmar 

August 19, 2009, 08:09 

#6  
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Glenn Horrocks
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