PartialDistributedVolume

Base class for distributed volume models

Information

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

Interface and base class for n ideally mixed fluid volumes with the ability to store mass and energy. It is intended to model a one-dimensional spatial discretization of fluid flow according to the finite volume method. The following boundary flow and source terms are part of the energy balance and must be specified in an extending class:

  • Qb_flows[n], heat flow term, e.g., conductive heat flows across segment boundaries, and
  • Wb_flows[n], work term.

The component volumes fluidVolumes[n] are an input that needs to be set in an extending class to complete the model.

Further source terms must be defined by an extending class for fluid flow across the segment boundary:

  • Hb_flows[n], enthalpy flow,
  • mb_flows[n], mass flow,
  • mbXi_flows[n], substance mass flow, and
  • mbC_flows[n], trace substance mass flow.

Parameters (13)

n

Value: 2

Type: Integer

Description: Number of discrete volumes

energyDynamics

Value: system.energyDynamics

Type: Dynamics

Description: Formulation of energy balances

massDynamics

Value: system.massDynamics

Type: Dynamics

Description: Formulation of mass balances

substanceDynamics

Value: massDynamics

Type: Dynamics

Description: Formulation of substance balances

traceDynamics

Value: massDynamics

Type: Dynamics

Description: Formulation of trace substance balances

p_a_start

Value: system.p_start

Type: AbsolutePressure (Pa)

Description: Start value of pressure at port a

p_b_start

Value: p_a_start

Type: AbsolutePressure (Pa)

Description: Start value of pressure at port b

ps_start

Value: if n > 1 then linspace(p_a_start, p_b_start, n) else {(p_a_start + p_b_start) / 2}

Type: AbsolutePressure[n] (Pa)

Description: Start value of pressure

use_T_start

Value: true

Type: Boolean

Description: Use T_start if true, otherwise h_start

T_start

Value: if use_T_start then system.T_start else Medium.temperature_phX((p_a_start + p_b_start) / 2, h_start, X_start)

Type: Temperature (K)

Description: Start value of temperature

h_start

Value: if use_T_start then Medium.specificEnthalpy_pTX((p_a_start + p_b_start) / 2, T_start, X_start) else Medium.h_default

Type: SpecificEnthalpy (J/kg)

Description: Start value of specific enthalpy

X_start

Value: Medium.X_default

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

Description: Start value of mass fractions m_i/m

C_start

Value: Medium.C_default

Type: ExtraProperty[Medium.nC]

Description: Start value of trace substances

Inputs (1)

fluidVolumes

Type: Volume[n] (m³)

Description: Discretized volume, determine in inheriting class

Components (2)

system

Type: System

Description: System properties

mediums

Type: BaseProperties[n]

Extended by (1)

PartialTwoPortFlow

Modelica.Fluid.Pipes.BaseClasses

Base class for distributed flow models