The Force Accumulator subnode is available from the context menu (right-click the Wall node) or from the Physics toolbar, Attributes menu. Each Force Accumulator subnode is a special type of boundary accumulator that accumulates normal contact force on the wall element during the contact between the grain and the wall.

Enter the Accumulated variable name. The default is wf. The accumulated variable is defined as <scope>.<name>, where <scope> includes the name of the physics interface node, parent boundary condition, and the Force Accumulator node; and <name> is the accumulated variable name.

For example, if the Force Accumulator subnode is added to a Wall node in an instance of the Granular Flow interface using the default variable name wf, the accumulated variable name might be gran.wp.facc1.wf.

See Accumulator (Boundary) for settings related to Grain Selection.