user defined functions

avion · March 17, 2009, 18:37

Hey
im trying to create a velocity function that is dependent on time and also the inlet diameter of a tube....creating in fluent

i have no clue how to implement the diameter as a function and also how to make velocity a function of two variables...

can some one please help me out

regards

Av

technocrat.prakash · March 17, 2009, 18:51

You can do it. Its 2D or 3D.

I have explained it for 2D.

First for time, you can get the value from *time definition.

Second for knowing the diameter, just loop over the inlet wall (the diameter) cells. For each cell try to find the length of the cell and sum it to find the dia.

All the best!

March 17, 2009, 18:37	user defined functions	#1
avion New Member AV Join Date: Mar 2009 Posts: 3 Rep Power: 17	Hey im trying to create a velocity function that is dependent on time and also the inlet diameter of a tube....creating in fluent i have no clue how to implement the diameter as a function and also how to make velocity a function of two variables... can some one please help me out regards Av

March 17, 2009, 18:51	Udf	#2
technocrat.prakash New Member Prakash Ayappan Join Date: Mar 2009 Posts: 25 Rep Power: 17	You can do it. Its 2D or 3D. I have explained it for 2D. First for time, you can get the value from *time definition. Second for knowing the diameter, just loop over the inlet wall (the diameter) cells. For each cell try to find the length of the cell and sum it to find the dia. All the best!

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