✅ ANSYS FLUENT - UDF Tutorial (Temperature Profile)

In this tutorial, you will learn how to use a basic UDF file, compile, and modify it.
#AnsysFluent #AnsysFluentUDF #CFDNinja

Computational Fluid Dynamics
ANSYS

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[naveenpandrinki]

Hi, I have problem regarding temperature distribution along channel. Have given heat flux but there is no temperature raise in materials . What was the problem

[eng.renatocarvalho]

Thanks very much for these tutorials from your channel. I couldn't import the mesh you've done.. I don't know why actually. That wasn't a problem though because I've watched many of yours videos and I already have enough knowledge to create my own geometry and mesh by using intuition when defining the dimensions. Everything worked out well and I've learned the main points of your tutorial that is using a temperature profile through a UDF! Thanks again! You are helping a lot to build my experience in CFD using Fluent!

[ashleymason]

thank u for the help i've been looking for.
But suppose your length is 200mm and u want temperature distribution till 100mm, what change u will do in the udf ?

[juanarriaga]

Hi is there a way to model an energy profile? As in like a point heat source to melt an object?

[felipeluz]

How to program a heat flux distribution in a radial section, like a pipe wall? I'm designing a parabolic trough collector then I need to input the corret heat flux distribution there. Can you help me?

[beka]

Any tutorial on UDF for CFD-post (e.g. integration along a domain) Thank you!

[jokhioization]

paid work, combustion of biomass By UDF, how can i contact you?

[sayedaislam]

Will it be a problem if I install Ansys in G drive and Visual Studio in C drive? Because even though i have followed all the instruction that you have given to avoid the "nmake" error, it still shows error. What can I do now?

[aliabbas]

hello thank you for this tutorial; currently i am working on thermal modeling of lithium ion battery can you please help me with the part related to the udf to create a heat source?

[angelpenev]

Great video! May I use this kind of code if I want to make a profile temperature function of time and tihs temperature will be on the inlet velocity. The flow is transient and laminar. Thank you.

[samking]

I want to write a UDF for non-uniform heat flux around a cylinder. I have the function in terms of theta but facing problems while writing a UDF. Can you help me out ?

[faiqshahid]

Hey, I am working on the CFD of axial flow turbine in ansys CFX, I want to define a UDF for non uniform temperature at turbine inlet, can you help me out with that?

[ziadsalloomi]

Hi,

First of all, I would like to say a big thanks for the awesome work that comes from the website and this channel.
I have to simulate a flow around a 3d cylinder with the bottom-mounted on the floor of the domain. I was wondering if you have a tutorial on this type of simulation?

Also, I have to apply a boundary condition at the inlet with a boundary layer thickness δ/d=0.6; Do you have a video about this as well?

Kind regards,

[viveksankurubhukta]

I am running a 2D transient simulation(VOF Fluent) in which vapor bubbles are generated at the bottom surface of a rectangular domain that is initially full of water with heat flux given at the bottom wall. I was trying to patch a single vapor bubble by creating a hemispherical region. I can see my volume fraction contour with the bubble after patching a hemispherical region at the bottom of the liquid. The simulation is also running perfectly when I click on "Run Calculation".
When I do this same bubble patch operation through a DEFINE_INIT UDF, I can see the bubble getting patched in the vapor phase contour, but the calculation is not running. It is giving the following error in the 1st iteration itself.
Divergence detected in AMG solver: vof-1
Divergence detected in AMG solver: x-momentum
Divergence detected in AMG solver: y-momentum
Divergence detected in AMG solver: pressure correction
Divergence detected in AMG solver: pressure correction
Divergence detected in AMG solver: temperature

UDF code
#include "udf.h"

DEFINE_INIT (init2, domain1)
{
Message("solution initialised");


cell_t cell;
Thread *cell_thread;
Domain *subdomain;

int phase_domain_index;
//Initialisation of heater layer

sub_domain_loop(subdomain, domain1, phase_domain_index)
{

if(DOMAIN_ID(subdomain) == 2)
{
thread_loop_c (cell_thread, subdomain)
{

begin_c_loop_all (cell, cell_thread)
{
real arr[ND_ND];
C_CENTROID(arr, cell, cell_thread);
if (sqrt(ND_SUM(pow(arr[0], 2), pow(arr[1], 2),
{

C_VOF (cell, cell_thread) = 0. ;
C_P(cell, cell_thread)= 5846400;
}

else
{

C_VOF (cell, cell_thread) = 1. ;
}

}
end_c_loop_all (cell, cell_thread);

}

}



}
}

When I am running the calculation I am getting this error, but there is no error when I am patching it without udf by creating a region.
I want this patching operation to be done via udf, so I can generate new bubbles after every time step in a specific pattern. (I will be using EXECUTE_AT_END for that ). I would be grateful if you can help me sir.

[ja_]

Thank you! I would like to know how to implement a UDF that enables the computation of residence time inside a reactor (I need it in order to find the stagnant zones). Thank you very much in advance!

[marwasaood]

Hello, I am doing a simulation of the pipe. Water with a constant heat flux in the case of the transiet. The wall does not heat up. Can someone help me?

[dir]

Hey Ninja, can u make a tutorial, how to calculate pressure recovery coefficient for super sonic flow. For example i would like to calculate pressure recovery in super sonic intake with normal shock losses.

[gaganrastogi]

I Have a Vertical 2D Wall, Boundary Condition for the wall is Non Isothermal, varying with respect to Position only, Not With Respect to Time. How can i add this boundary condition ?

[muzilee]

hello ， how can i change the working direction in workbench ?

[bilkanjohnhemrom]

i'm using VS19 and Ansys fluent 19.2 to solve this problem. udf is building successfully but while loading it, it is showing following error. why it so?
Error: The UDF library you are trying to load (libudf) is not compiled for parallel use on the current platform (win64).\n\nThe system cannot find the file specified.
tube\circular
Error Object: #f