Accumulator (Boundary)

The subnode is available from the context menu (right-click the Wall or Material Discontinuity parent node) or from the toolbar, menu. Each subnode defines a variable, called the accumulated variable, on each boundary element in the selection of the parent node. The accumulated variables are incremented when rays interact with the boundaries where they are defined.

Select an option from the list: (default) or .

•

For the accumulated variable is divided by the surface area of the boundary element where it is defined.

•

For the accumulated variable is the sum of the source terms of all rays that hit the boundary element, and is unaffected by the boundary element size.

Select an option from the list: (the default) or .

•

For the accumulated variable is affected by all rays that hit the boundary element.

•

For the accumulated variable is only affected by rays that freeze or stick to the boundary element.

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

For example, if the subnode is added to a Wall node in an instance of the Geometrical Optics interface using the default variable name rpb, the accumulated variable name might be gop.wall1.bacc1.rpb.

Enter a R. The unit of the source term depends on the settings in the section. Whenever a ray collides with a boundary element in the selection of the parent node, the accumulated variable in that element is incremented by the source term. If the is set to , the source term is divided by the area of the boundary element (in 3D) or the length of the boundary element (in 2D).

For example, if the source is 1 and is selected from the list, a variable is created to store the number of times each boundary element is hit by a ray.

Select a from the list; the default is . To enter a unit, select from the list and in the field enter a value, for example, K, m/s, or mol/m^3.

The accumulated variables are computed using discontinuous shape functions. Select the check box to compute a smoothed accumulated variable by computing the average value of the variable within a sphere of a user-defined radius. Then enter a r (SI unit: m). The default is 1 m.