A diaphragm (Figure 118) is characterized by head losses of the form:
where is a head loss coefficient depending on the ratio , is the mass flow, g is the gravity acceleration and is the liquid density. and are the cross section of the diaphragm and of the pipe, respectively. Values for can be found in file ``liquidpipe.f''.
The following constants have to be specified on the line beneath the *FLUID SECTION, TYPE=PIPE DIAPHRAGM card:
The gravity acceleration must be specified by a gravity type *DLOAD card defined for the elements at stake. The material characteristic can be defined by a *DENSITY card.