The swirlFlowRateInletVelocity is a velocity boundary condition that provides a volumetric- or mass-flow normal vector boundary condition by its magnitude as an integral over its area with a swirl component determined by the angular speed, given in revolutions per minute (RPM).

The basis of the patch (volumetric or mass) is determined by the dimensions of the flux, phi. The current density is used to correct the velocity when applying the mass basis.


The condition requires entries in both the boundary and field files.

Boundary file

    type            patch;

Field file

    // Mandatory entries
    type           swirlFlowRateInletVelocity;
    flowRate       <Function1<scalar>>;
    rpm            <Function1<scalar>>;

    // Optional entries
    phi            <word>;
    rho            <word>;
    origin         <vector>;
    axis           <vector>;

    // Inherited entries


Property Description Type Required Default
type Type name: swirlFlowRateInletVelocity word yes -
flowRate Flow rate profile Function1<scalar> yes -
rpm Rotational speed profile Function1<scalar> yes -
phi Name of the flux field word no phi
rho Name of the density field word no rho
origin Origin of rotation vector no Zero
axis Axis of rotation vector no Zero

The inherited entries are elaborated in:

Further information


  • N/A

Source code:



  • Introduced in version 1.7.0