When you load the Brayton Cycle Model , A Model Callback is already defined to load variables,these variables values are defined in the PreLoadFcn Callback which can be viewed going on to the Modeling tab, then click Model Settings > Model Properties > PreLoadFcn.
Each time that you open the model, the PreLoadFcn callback loads the variables into the MATLAB workspace.
If you wish to do so you can also edit the variables , remove the variables or even add new variables in this PreLoadFcn callback which has been defined.
You can also load the variables defined seperately in a different MATLAB script into this Model by just entering the name of the M-script in the Callback Function.
To know more about the various types of Model Callbacks and how to make use of them refer to this link.
