4.2 Loading the MHD Module

The MHD module is loaded into ANSYS FLUENT through the text user interface (TUI). The module can only be loaded when a valid ANSYS FLUENT case file has been set or read. The text command to load the module is

define $\rightarrow$ models $\rightarrow$ addon-module.

A list of ANSYS FLUENT addon modules is displayed:

FLUENT Addon Modules:
	0. none
	1. MHD Model
	2. Fiber Model
	3. Fuel Cell and Electrolysis Model
	4. SOFC Model with Unresolved Electrolyte
	5. Population Balance Model
Enter Module Number: [1] 1

Select the MHD model by entering the module number 1. During the loading process a scheme library containing the graphical and text user interface, and a udf library containing a set of user defined functions are loaded into ANSYS FLUENT. A message Addon Module: mhd...loaded! is displayed at the end of the loading process.

The basic setup of the MHD model is performed automatically when the MHD module is loaded successfully. The setup includes:

• Selecting the default MHD method

• Allocating the required number of user-defined scalars and memory locations

• naming of:
  • User-defined scalars and memory locations

  • All UDF Hooks for MHD initialization and adjustment

  • MHD equation flux and unsteady terms

  • Source terms for the MHD equations

  • Additional source terms for the fluid momentum and energy equations

  • Default MHD boundary conditions for external and internal boundaries

  • A default set of model parameters

• DPM related functions are also set if the DPM option has been selected in the ANSYS FLUENT case setup.

The MHD module setup is saved with the ANSYS FLUENT case file. The module is loaded automatically when the case file is subsequently read into ANSYS FLUENT. Note that in the saved case file, the MHD module is saved with the absolute path. Therefore, if the locations of the MHD module installation or the saved case file are changed, ANSYS FLUENT will not be able to load the module when the case file is subsequently read.

To unload the previously saved MHD module library, use the

Define $\rightarrow$ User-Defined $\rightarrow$ Functions $\rightarrow$ Manage...

menu and reload the module as described above. Note that the previously saved MHD model setup and parameters are preserved.