Iteration number at which to start fan simulation.

Iteration frequency to update the fan momentum source scale factor. The default is 250.

Underrelaxation of the momentum source terms governed by Eqns. (6) and (7), from one iteration to the next.

Sets the tolerance for the fan curve pressure drop for the simulation flow rate. If the simulation pressure drop is within this tolerance, the momentum scale factor is not updated.

Adjusts the momentum source scale factor, according to Eqn. 11.

Underrelaxation of updates of the momentum scale factor as described in Eqn. 11. This takes place between momentum scale factor updates, which happen every number of iterations as specified in the IUpdate property.

Controls the output of diagnostic data.

Upper limit on the flowrates used to calculate the momentum source terms. This property assists with the rate of convergence of the problem. If the maximum flowrate is set at less than the minimum flowrate, the momentum source terms are always calculated as if the volume flowrate were the minimum flowrate.

Lower limit on the flowrates used to calculate the momentum source terms. This property assists with the rate of convergence of the problem. The minimum flowrate is especially important to prevent the simulation fan from pushing air backwards, which is possible with the governing equations.

It is advisable to set this property greater than zero. The theory used for the fan momentum source is not applicable near fan stall (zero flow). The equations always predict zero pressure at zero flow.

In the cases where the flow is less than the minimum specified value, the Minimum Volume Flowrate causes the momentum source terms to provide force into the flow as if the flow were the minimum specified value.