*DFLOW

Optional parameters

AMPLITUDE

Set this parameter equal to the name of the AMPLITUDE curve that defines the magnitude of the seepage flow during the step. If this parameter is omitted for uniform seepage types, the reference magnitude is applied immediately at the beginning of the step or linearly over the step, depending on the value assigned to the AMPLITUDE parameter on the STEP option (see Defining an Analysis). Amplitude references are ignored for flows defined in user subroutine DFLOW.

OP

Set OP=MOD (default) for existing DFLOWs to remain, with this option modifying existing flows or defining additional flows.

Set OP=NEW if all existing DFLOWs applied to the model should be removed. New flows can be defined.

Data lines to define uniform seepage

First line

Element number or element set label.
Distributed seepage type label (see About the Element Library).
Reference seepage magnitude. (Units of LT⁻¹.) The seepage magnitude is the pore fluid effective velocity crossing the surface at this point in an outward direction.

Repeat this data line as often as necessary to define uniform seepage for various elements or element sets.

Data lines to define nonuniform seepage

First line

Element number or element set label.
Distributed seepage type label (see About the Element Library).
Seepage magnitude (optional). If given, this value is passed into user subroutine DFLOW in the variable used to define the seepage magnitude.

Nonuniform seepage magnitudes are defined via user subroutine DFLOW.

Repeat this data line as often as necessary to define nonuniform seepage for various elements or element sets.