Monitor Integral

For example, if you have defined a monitor for the mass flow through some boundary, this report can compute the integral of that mass flow over time. A monitor integral report can also be the subject of another monitor, and thus its values can be displayed in a chart, or be printed to the output while iterating.

The monitor integral report can work with any monitor that can be plotted, including report monitors, residual monitors, physical time monitors, and the iteration monitor.

Additionally, the monitors you choose can have different update frequencies and starting triggers. If, for example, you have an integrand monitor that updates every 5 iterations starting at iteration 1, and a variable monitor that updates every 3 iterations starting at iteration 16, the computation of the integral only accounts for iterations {16, 31, 46, 61, ... } as these are the only iterations on which both monitors have data. It is possible to set up two monitors that have the same update frequency, but different starting triggers, such that they never update on the same iteration. In this case, there is no data from which to compute the integral.

This report uses unnormalized data, so it does not take into account the Normalization Option setting of its input monitors.

Monitor Integral Report Properties

Units

The units are that of the resulting integration, and are (in effect) the product of the units of the integrand and the units of the integration variable. So if you integrate velocity (in meters/second) as a function of time (in seconds), the final units are in meters, since (m/s) * (s) = m. The drop-down list displays all units known to the simulation that are dimensionally compatible with the integration—including user-defined units.

Integrand

The monitor whose quantity is integrated over the Variable quantity.

Variable

The monitor that serves as the independent quantity of the integration.

Sample collection policy

Specifies whether the report is on all samples or the last N samples, where N is specified in the Last N Samples child node. The default is All samples.

Child Node Properties

The monitor integral report node has a child node named either All samples or Last N Samples, depending on the selection made under Sample collection policy.

Sample count

The number of data samples N collected for each cell within the monitor. For the Last N Samples node only. For multiple inputs, the report collects enough samples from the input monitors so that there are N iterations in common across all of them. The report then runs on these N common iterations.

Sample start event

The event at which to begin collecting data. See User-Defined Update Events.

Include start event sample

When On, includes the sample at a start event in the sample collection.