[hydraulic]

Hi All,
I need some help with the CFX functions.
I would like to run a transient simulation by reading a csv file every time step.
Until now, I was computing only steady state by reading .csv files which look like:

[Data]
x [ m ],y [ m ],z [ m ],Velocity [ m s^-1 ], Temperature [ K ]...
0, 1, 15, 5, 284.211
1, 2, 15, 1, 284.55
...

My User functions look like:
LIBRARY: CEL:
&replace FUNCTION: Top
Argument Units = [m], [m], [m]
File Name = myPath/Top.csv
Option = Profile Data
Profile Function = On
Render Type = Points
Spatial Fields = x, y, z
DATA FIELD: Temperature Field Name = Temperature
Result Units = [K]
END
DATA FIELD: Velocity
Field Name = Velocity
Result Units = [m s^-1]
END
END

Now i would like to switch to transient simulations and read a file for every time step (delta t=1s). Does someone has a Tipp how to do that?
My first idea was to change in the csv files my x,y,z with x,y,t as my boundaries can be defined with only 2 coordinates. The input file become:

x [ m ],y [ m ],t[ s ],Velocity [ m s^-1 ], Temperature [ K ]...
0, 1, 0, 5, 284.211
1, 2, 0,1, 284.55...
0, 1, 1, 5, 284.211
1, 2, 1, 1, 284.55...

Do you have an idea how to read the new files by doing an interpolation with respect to time?

Thanks in advance!

[ghorrocks]

First of all - if the function is known in advance it can be entered as a CEL expression. But I assume the function is complex enough that this is not practical.

I think you are going to have to do write a user fortran function to do this. Have a look at the example user fortran examples in the CFX documentation on how to do this.

[Lance]

Originally Posted by hydraulic

My first idea was to change in the csv files my x,y,z with x,y,t as my boundaries can be defined with only 2 coordinates. The input file become:
x [ m ],y [ m ],t[ s ],Velocity [ m s^-1 ], Temperature [ K ]...
0, 1, 0, 5, 284.211
1, 2, 0,1, 284.55...
0, 1, 1, 5, 284.211
1, 2, 1, 1, 284.55...
Do you have an idea how to read the new files by doing an interpolation with respect to time?

This will work, Iam pretty sure I have done it previously. CFX will interpolate in time if you call your function with the arguments (x,y,t).