Nonlocal Accumulator

Use the subnode to communicate information from a ray’s current position to the position from which it was released.

The subnode is available from the context menu (right-click the Release from Boundary parent node) or from the toolbar, menu.

Each subnode defines a variable, called the accumulated variable, that is computed using variables defined on rays released by the parent node or on domains and boundaries encountered by such rays.

Accumulator Settings

Select an : (default) or .

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For the accumulated variable is divided by the volume of the mesh element where it is defined.

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For the accumulated variable is unaffected by the element size.

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

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For the accumulated variable is proportional to the instantaneous value of the term R for all applicable rays.

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For the time derivative of the accumulated variable is proportional to the instantaneous value of the term R for all applicable rays, and thus the accumulated variable considers the time history of rays in the modeling domain instead of just their current values.

Enter the . The default is rpi.

Enter a R. The unit of the source depends on the settings in the section. The source term is used to calculate the accumulated variable in a manner specified by the and settings.

Select a : , , or .

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If is selected, rays only contribute to the accumulated variable on their releasing surface while they are active (still propagating through a domain).

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If is selected, the rays only contribute to the accumulated variable if they have become stuck or frozen to a boundary somewhere in the model.

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If is selected, all of the active, stuck, and frozen rays released by a feature can contribute to the accumulated variable.

Units

Select a from the list; the default is . To enter a unit, select from the list and in the field enter a value.

Smoothing

Select the check box to enter a r (SI unit: m). The default is 0.1 m.