Average and Integral

) or (

) data set, found under the submenu, to compute the average or integral of another data set, for example, to plot the average or integral.

Select a for the data to compute the average or integral. To compute the average or integral for a data set, use a to define the geometric entity (point, boundary, edge, or domain) to integrate over. Right-click the data set and select .

Select an integration : (the default), , or .

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— Computes the integral for fields by numerical integration and for reaction forces by summation. Predefined quantities for reaction forces use summation instead of integration. Also, to specify an expression for the integrand, use the reacf operator, and the automatic setting chooses the summation method.

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— a summation method useful for computing reaction forces. The summation method finds all nodes on the boundary, evaluates the expression in the nodes and sums up the values. Reaction force variables are predefined in the structural mechanics interfaces. This is selected instead of Integration for reaction forces when the automatic selection of integration method is active.

For , the COMSOL Multiphysics software determines an appropriate integration order for the expression when you use integration. The default is 4. Select the check box to make a different entry in the field (as an integer that is 0 or larger). COMSOL Multiphysics then performs the integration elementwise using numeric quadrature of the selected order.

Select a — (the default), , , , or . The default means the highest geometry dimension for the data in the data set; typically volumes in 3D, surfaces in 2D, and lines in 1D.

If the data set represents data for a 1D or 2D axisymmetric geometry, select the (1D axial symmetry) or (2D axial symmetry) check box to compute an average or integral that takes the axial symmetry into account. COMSOL Multiphysics then multiplies the expression (integrand) with 2*pi*r prior to integration to compute the corresponding volume or surface integral.