Ansys Fluent – UDF (User-Defined Function) Temperature Profile

A user-defined function, or UDF, is a function that you program that can be dynamically loaded with the ANSYS FLUENT solver to enhance the standard features of the code. For example, you can use a UDF to define your own boundary conditions, material properties, and source terms for your flow regime, as well as specify customized model parameters (e.g., DPM, multiphase models), initialize a solution, or enhance postprocessing.

UDFs are written in the C programming language using any text editor and the source code file is saved with a .c extension (e.g., myudf.c). One source file can contain a single UDF or multiple UDFs, and you can define multiple source files.

Every UDF must contain the udf.h file inclusion directive ( #include "udf.h") at the beginning of the source code file, which allows definitions of DEFINE macros and other ANSYS FLUENT-provided macros and functions to be included during the compilation process.

Source files containing UDFs can be either interpreted or compiled in ANSYS FLUENT. For interpreted UDFs, source files are interpreted and loaded directly at runtime, in a single-step process. For compiled UDFs, the process involves two separate steps. A shared object code library is first built and then it is loaded into ANSYS FLUENT.

In this tutorial you will learn to compile UDF (User-Defined Function)  using Ansys Fluent. In this case, we have a UDF about temperature profile. You can download the file from this link.