Boundary_ph

Boundary with prescribed pressure, specific enthalpy, composition and trace substances

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

Defines prescribed values for boundary conditions:

  • Prescribed boundary pressure.
  • Prescribed boundary temperature.
  • Boundary composition (only for multi-substance or trace-substance flow).

If use_p_in is false (default option), the p parameter is used as boundary pressure, and the p_in input connector is disabled; if use_p_in is true, then the p parameter is ignored, and the value provided by the input connector is used instead.

The same thing goes for the specific enthalpy and composition

Note, that boundary temperature, mass fractions and trace substances have only an effect if the mass flow is from the boundary into the port. If mass is flowing from the port into the boundary, the boundary definitions, with exception of boundary pressure, do not have an effect.

Parameters (9)

nPorts

Value: 0

Type: Integer

Description: Number of ports

use_p_in

Value: false

Type: Boolean

Description: Get the pressure from the input connector

use_h_in

Value: false

Type: Boolean

Description: Get the specific enthalpy from the input connector

use_X_in

Value: false

Type: Boolean

Description: Get the composition from the input connector

use_C_in

Value: false

Type: Boolean

Description: Get the trace substances from the input connector

p

Value: Medium.p_default

Type: AbsolutePressure (Pa)

Description: Fixed value of pressure

h

Value: Medium.h_default

Type: SpecificEnthalpy (J/kg)

Description: Fixed value of specific enthalpy

X

Value: Medium.X_default

Type: MassFraction[Medium.nX] (kg/kg)

Description: Fixed value of composition

C

Value: Medium.C_default

Type: ExtraProperty[Medium.nC]

Description: Fixed values of trace substances

Connectors (5)

ports

Type: FluidPorts_b[nPorts]

p_in

Type: RealInput

Description: Prescribed boundary pressure

h_in

Type: RealInput

Description: Prescribed boundary specific enthalpy

X_in

Type: RealInput[Medium.nX]

Description: Prescribed boundary composition

C_in

Type: RealInput[Medium.nC]

Description: Prescribed boundary trace substances

Components (1)

medium

Type: BaseProperties

Description: Medium in the source