In order to perform mass transfer analyses, an Autodesk Simulation Multiphysics license is required. This feature is unavailable in Autodesk Simulation Mechanical.
In this section, we cover aspects of setting up and performing the analysis that are specific to mass transfer analyses. Much of the setup process is common to other analysis types. Therefore, first check the General Information (Common to Multiple Analysis Types) section of the Help. If an item pertains to two or more analysis categories, it will be covered in the General Information section. Otherwise, if an item only pertains to a specific analysis type, it will be covered within the Analysis-Specific Information section of the Help.
In some cases, a particular topic might be addressed in both the General and Analysis-Specific sections. This can occur when an item is applicable to two or more analysis types and there are similarities or overlap between them - which will be covered in the General section - as well as significant differences between the analysis types, which are best handled in the analysis-specific section.
Unique Model Setup Requirement for Mass Transfer
The setup of a mass transfer model has one requirement that other analysis types do not have. In mass transfer, the global Species that exist in the entire model must be defined before:
- assigning the Species Definition (equivalent to the Element Definition for other analysis types) to each part,
- applying loads and constraints to the model.
If the global Species are not defined first, then specifying which species appears in each part cannot be done, and loads cannot be applied to the model.
The Species branch of the tree view is a list of all species or materials that appear in any part of the model. To define the species, do the following:
- Right-click the Species entry in the tree view and choose Add New Species. The Creating Mass Species dialog will appear.
- Enter the Name of the species. (This name will appear in the other dialogs, so each species should have a unique name.)
- Enter the Default Diffusivity of the species. The default will be used for each species in each part unless you explicitly changes it in a given part.
NoteThe mass transfer analysis is calculating the concentration of substance A within substance X, substance B within substance X, and so on. Substance X is not one of the species in the analysis. Likewise, the diffusivity is based on the substance within substance X.
Once they are created, individual species can be modified or deleted by right-clicking on the species in the global Species branch.