UDF starter
 

Hi,

I'm trying to write my own UDF. I'm not getting anything from the FLUENT user guide.

Someone please help me with some example. How could i proceed in writing my own UDF.

Tell us what you want to achieve with the UDF.
Then we can be a little more specific with the guidance we provide.

Udf
 

Hi,

I'm new to UDF.

I'm trying to simulate a moving wall over a fluid.

Can u help me.

The possibilities with UDFs are nearly infinite.
So is the range of complexity of UDFs.

Before you start writing a UDF, you should know what it is supposed to do.

New question of dynamic mesh-udf
 

HELLO
i want to use dynamic mesh to simulate a motion of a microorganism.i have understood that i have to write a UDF to define a motion of microorganism for fluent.i have 6 pictures(including data of positions) of microorganism in one cycle of its swimming motion.now these are my questions:
1- what my program suppose to do?(i am actually a little confused about it)
2- Do i have to interpolate to find the position of nodes through the time?
3-Do i need to calculate the velocity and acceleration of nodes too?(i only have data for positions)
4-which marcos should i use?
i have read the UDF manual but i didnt get whole of it.I would be thankful for any help from you?

Udf
 

Let us take an example of landing of aircraft(from certain height till its completely lands).

Is it need to define a UDF . If yes how to start.

I tell you again I'm new to UDF.

So, It would be helpful if you help in some basics steps how to write a UDF.

I feel like we are speaking different languages here.
The landing of an aircraft provides about a trillion possibilities for the use of UDFs. Since the setup of the simulation is not even defined, I could only guess what the application of a UDF in this context could be.

The range is from setting a time-variant density ot the fluid to defining the movement of the landing flaps.
I am very sorry, but I can't provide any guidance about a topic that is totally vague.

Udf
 

Hi,

Just tell me how to write a time dependent B.C's using UDF.

The problem is like flow of a water in a tank.

udf
 

Hi Vignesh

Read DEFINE_PROFILE macro. One UDF for already written for spatial variation of velocity for the flow over aerofoil. In this profile make some modifications like - first call and specify the real time as time variable 't' and change the equation of your kind with time variable 't'.

best wishes
Mvee