Valve model according to the IEC 534/ISA S.75 standards for valve sizing, incompressible fluid at the inlet, and possibly two-phase fluid at the outlet, including choked flow conditions.
The parameters of this model are explained in detail in PartialValve (the base model for valves).
The model operating range includes choked flow operation, which takes place for low outlet pressures due to flashing in the vena contracta; otherwise, non-choking conditions are assumed.
This model requires a two-phase medium model, to describe the liquid and (possible) two-phase conditions.
The default liquid pressure recovery coefficient Fl is constant and given by the parameter Fl_nominal. The relative change (per unit) of the recovery coefficient can be specified as a given function of the valve opening by replacing the FlCharacteristic function.
If checkValve is false, the valve supports reverse flow, with a symmetric flow characteristic curve. Otherwise, reverse flow is stopped (check valve behaviour).
The treatment of parameters Kv and Cv is explained in detail in the User's Guide.
| Name | Description |
|---|---|
| FlCharacteristic | Pressure recovery characteristic |