Modelica.Fluid.Vessels

Devices for storing fluid

Information



Extends from Modelica.Icons.VariantsPackage (Icon for package containing variants).

Package Content

NameDescription
Modelica.Fluid.Vessels.ClosedVolume ClosedVolume Volume of fixed size, closed to the ambient, with inlet/outlet ports
Modelica.Fluid.Vessels.OpenTank OpenTank Simple tank with inlet/outlet ports
Modelica.Fluid.Vessels.BaseClasses BaseClasses Base classes used in the Vessels package (only of interest to build new component models)

Modelica.Fluid.Vessels.ClosedVolume Modelica.Fluid.Vessels.ClosedVolume

Volume of fixed size, closed to the ambient, with inlet/outlet ports

Information


Ideally mixed volume of constant size with two fluid ports and one medium model. The flow properties are computed from the upstream quantities, pressures are equal in both nodes and the medium model if use_portsData=false. Heat transfer through a thermal port is possible, it equals zero if the port remains unconnected. A spherical shape is assumed for the heat transfer area, with V=4/3*pi*r^3, A=4*pi*r^2. Ideal heat transfer is assumed per default; the thermal port temperature is equal to the medium temperature.

If use_portsData=true, the port pressures represent the pressures just after the outlet (or just before the inlet) in the attached pipe. The hydraulic resistances portsData.zeta_in and portsData.zeta_out determine the dissipative pressure drop between volume and port depending on the direction of mass flow. See VesselPortsData and [Idelchik, Handbook of Hydraulic Resistance, 2004].

Extends from Modelica.Fluid.Vessels.BaseClasses.PartialLumpedVessel (Lumped volume with a vector of fluid ports and replaceable heat transfer model).

Parameters

NameDescription
replaceable package MediumMedium in the component
fluidVolumeVolume [m3]
VVolume [m3]
Ports
use_portsData= false to neglect pressure loss and kinetic energy
portsData[if use_portsData then nPorts else 0]Data of inlet/outlet ports
Assumptions
Dynamics
energyDynamicsFormulation of energy balance
massDynamicsFormulation of mass balance
Heat transfer
use_HeatTransfer= true to use the HeatTransfer model
replaceable model HeatTransferWall heat transfer
Initialization
p_startStart value of pressure [Pa]
use_T_start= true, use T_start, otherwise h_start
T_startStart value of temperature [K]
h_startStart value of specific enthalpy [J/kg]
X_start[Medium.nX]Start value of mass fractions m_i/m [kg/kg]
C_start[Medium.nC]Start value of trace substances
Advanced
Port properties
m_flow_nominalNominal value for mass flow rates in ports [kg/s]
m_flow_smallRegularization range at zero mass flow rate [kg/s]
use_Re= true, if turbulent region is defined by Re, otherwise by m_flow_small

Connectors

NameDescription
ports[nPorts]Fluid inlets and outlets
heatPort 

Modelica.Fluid.Vessels.OpenTank Modelica.Fluid.Vessels.OpenTank

Simple tank with inlet/outlet ports

Information


Model of a tank that is open to the ambient at the fixed pressure p_ambient.

The vector of connectors ports represents fluid ports at configurable heights, relative to the bottom of tank. Fluid can flow either out of or in to each port.

The following assumptions are made:

The port pressures represent the pressures just after the outlet (or just before the inlet) in the attached pipe. The hydraulic resistances portsData.zeta_in and portsData.zeta_out determine the dissipative pressure drop between tank and port depending on the direction of mass flow. See VesselPortsData and [Idelchik, Handbook of Hydraulic Resistance, 2004].

With the setting use_portsData=false, the port pressure represents the static head at the height of the respective port. The relationship between pressure drop and mass flow rate at the port must then be provided by connected components; Heights of ports as well as kinetic and potential energy of fluid entering or leaving are not taken into account anymore.

Extends from Modelica.Fluid.Vessels.BaseClasses.PartialLumpedVessel (Lumped volume with a vector of fluid ports and replaceable heat transfer model).

Parameters

NameDescription
heightHeight of tank [m]
crossAreaArea of tank [m2]
replaceable package MediumMedium in the component
fluidVolumeVolume [m3]
Ports
use_portsData= false to neglect pressure loss and kinetic energy
portsData[if use_portsData then nPorts else 0]Data of inlet/outlet ports
Assumptions
Ambient
p_ambientTank surface pressure [Pa]
T_ambientTank surface Temperature [K]
Dynamics
energyDynamicsFormulation of energy balance
massDynamicsFormulation of mass balance
Heat transfer
use_HeatTransfer= true to use the HeatTransfer model
replaceable model HeatTransferWall heat transfer
Initialization
level_startStart value of tank level [m]
p_startStart value of pressure [Pa]
use_T_start= true, use T_start, otherwise h_start
T_startStart value of temperature [K]
h_startStart value of specific enthalpy [J/kg]
X_start[Medium.nX]Start value of mass fractions m_i/m [kg/kg]
C_start[Medium.nC]Start value of trace substances
Advanced
Port properties
m_flow_nominalNominal value for mass flow rates in ports [kg/s]
m_flow_smallRegularization range at zero mass flow rate [kg/s]
use_Re= true, if turbulent region is defined by Re, otherwise by m_flow_small

Connectors

NameDescription
ports[nPorts]Fluid inlets and outlets
heatPort 

Automatically generated Mon Sep 23 17:20:45 2013.