WOLFRAM SYSTEMMODELER

PartialTwoPortTransport

Partial element transporting fluid between two ports without storage of mass or energy

Wolfram Language

In[1]:=
SystemModel["Modelica.Fluid.Interfaces.PartialTwoPortTransport"]
Out[1]:=

Information

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

This component transports fluid between its two ports, without storing mass or energy. Energy may be exchanged with the environment though, e.g., in the form of work. PartialTwoPortTransport is intended as base class for devices like orifices, valves and simple fluid machines.

Three equations need to be added by an extending class using this component:

  • the momentum balance specifying the relationship between the pressure drop dp and the mass flow rate m_flow,
  • port_b.h_outflow for flow in design direction, and
  • port_a.h_outflow for flow in reverse direction.

Moreover appropriate values shall be assigned to the following parameters:

  • dp_start for a guess of the pressure drop
  • m_flow_small for regularization of zero flow.

Parameters (6)

allowFlowReversal

Value: system.allowFlowReversal

Type: Boolean

Description: = true to allow flow reversal, false restricts to design direction (port_a -> port_b)

dp_start

Value: 0.01 * system.p_start

Type: AbsolutePressure (Pa)

Description: Guess value of dp = port_a.p - port_b.p

m_flow_start

Value: system.m_flow_start

Type: MassFlowRate (kg/s)

Description: Guess value of m_flow = port_a.m_flow

m_flow_small

Value: if system.use_eps_Re then system.eps_m_flow * system.m_flow_nominal else system.m_flow_small

Type: MassFlowRate (kg/s)

Description: Small mass flow rate for regularization of zero flow

show_T

Value: true

Type: Boolean

Description: = true, if temperatures at port_a and port_b are computed

show_V_flow

Value: true

Type: Boolean

Description: = true, if volume flow rate at inflowing port is computed

Connectors (2)

port_a

Type: FluidPort_a

Description: Fluid connector a (positive design flow direction is from port_a to port_b)

port_b

Type: FluidPort_b

Description: Fluid connector b (positive design flow direction is from port_a to port_b)

Components (3)

system

Type: System

Description: System wide properties

state_a

Type: ThermodynamicState

Description: state for medium inflowing through port_a

state_b

Type: ThermodynamicState

Description: state for medium inflowing through port_b

Extended by (9)

PartialPressureLoss

Modelica.Fluid.Interfaces

Base flow model for pressure loss functions with the same area at port_a and at port_b

BaseModelNonconstantCrossSectionArea

Modelica.Fluid.Fittings.BaseClasses.QuadraticTurbulent

Generic pressure drop component with constant turbulent loss factor data and without an icon, for non-constant cross section area

BaseModel

Modelica.Fluid.Fittings.BaseClasses.QuadraticTurbulent

Generic pressure drop component with constant turbulent loss factor data and without an icon

SimpleGenericOrifice

Modelica.Fluid.Fittings

Simple generic orifice defined by pressure loss coefficient and diameter (only for flow from port_a to port_b)

VolumeFlowRate

Modelica.Fluid.Fittings.GenericResistances

Flow model for generic resistance parameterized with the volume flow rate

PartialValve

Modelica.Fluid.Valves.BaseClasses

Base model for valves

ValveDiscrete

Modelica.Fluid.Valves

Valve for water/steam flows with linear pressure drop

ValveLinear

Modelica.Fluid.Valves

Valve for water/steam flows with linear pressure drop

TestWallFrictionAndGravity

Modelica.Fluid.Pipes.BaseClasses.WallFriction

Pressure loss in pipe due to wall friction and gravity (only for test purposes; if needed use Pipes.StaticPipe instead)