Package Modelica.​Fluid.​Machines
Devices for converting between energy held in a fluid and mechanical energy

Information

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

Package Contents

NameDescription
BaseClassesBase classes used in the Machines package (only of interest to build new component models)
ControlledPumpCentrifugal pump with ideally controlled mass flow rate
PrescribedPumpCentrifugal pump with ideally controlled speed
PumpCentrifugal pump with mechanical connector for the shaft
SweptVolumevarying cylindric volume depending on the position of the piston

Model Modelica.​Fluid.​Machines.​SweptVolume
varying cylindric volume depending on the position of the piston

Information

Mixing volume with varying size. The size of the volume is given by:

Losses are neglected. The shaft power is completely converted into mechanical work on the fluid.

The flange position has to be equal or greater than zero. Otherwise the simulation stops. The force of the flange results from the pressure difference between medium and ambient pressure and the cross sectional piston area. For using the component, a top level instance of the ambient model with the inner attribute is needed.

The pressure at both fluid ports equals the medium pressure in the volume. No suction nor discharge valve is included in the model.

The thermal port is directly connected to the medium. The temperature of the thermal port equals the medium temperature. The heat capacity of the cylinder and the piston are not includes in the model.

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

Parameters

TypeNameDefaultDescription
AreapistonCrossArea Cross sectional area of piston
Volumeclearance Remaining volume at zero piston stroke
DynamicsenergyDynamicssystem.​energyDynamicsFormulation of energy balance
DynamicsmassDynamicssystem.​massDynamicsFormulation of mass balance
final DynamicssubstanceDynamicsmassDynamicsFormulation of substance balance
final DynamicstraceDynamicsmassDynamicsFormulation of trace substance balance
AbsolutePressurep_startsystem.​p_startStart value of pressure
Booleanuse_T_starttrue= true, use T_start, otherwise h_start
TemperatureT_startif use_T_start then system.T_start else Medium.temperature_phX(p_start, h_start, X_start)Start value of temperature
SpecificEnthalpyh_startif use_T_start then Medium.specificEnthalpy_pTX(p_start, T_start, X_start) else Medium.h_defaultStart value of specific enthalpy
MassFractionX_start[Medium.nX]Medium.​X_defaultStart value of mass fractions m_i/m
ExtraPropertyC_start[Medium.nC]Medium.​C_defaultStart value of trace substances
IntegernPorts0Number of ports
Booleanuse_portsDatatrue= false to neglect pressure loss and kinetic energy
VesselPortsDataportsData[if use_portsData then nPorts else 0] Data of inlet/outlet ports
MassFlowRatem_flow_nominalif system.use_eps_Re then system.m_flow_nominal else 100 * system.m_flow_smallNominal value for mass flow rates in ports
MassFlowRatem_flow_smallif system.use_eps_Re then system.eps_m_flow * m_flow_nominal else system.m_flow_smallRegularization range at zero mass flow rate
Booleanuse_Resystem.​use_eps_Re= true, if turbulent region is defined by Re, otherwise by m_flow_small
Booleanuse_HeatTransferfalse= true to use the HeatTransfer model

Connectors

TypeNameDescription
VesselFluidPorts_bports[nPorts]Fluid inlets and outlets
HeatPort_aheatPort 
Flange_bflangetranslation flange for piston

Model Modelica.​Fluid.​Machines.​Pump
Centrifugal pump with mechanical connector for the shaft

Information

This model describes a centrifugal pump (or a group of nParallel pumps) with a mechanical rotational connector for the shaft, to be used when the pump drive has to be modelled explicitly. In the case of nParallel pumps, the mechanical connector is relative to a single pump.

The model extends PartialPump

Extends from Modelica.​Fluid.​Machines.​BaseClasses.​PartialPump (Base model for centrifugal pumps).

Parameters

TypeNameDefaultDescription
BooleanallowFlowReversalsystem.​allowFlowReversal= true to allow flow reversal, false restricts to design direction (port_a -> port_b)
AbsolutePressurep_a_startsystem.​p_startGuess value for inlet pressure
AbsolutePressurep_b_startp_a_startGuess value for outlet pressure
MassFlowRatem_flow_startsystem.​m_flow_startGuess value of m_flow = port_a.m_flow
final VolumeFlowRateV_flow_single_initm_flow_start / rho_nominal / nParallelUsed for simplified initialization model
final Heightdelta_head_initflowCharacteristic(V_flow_single_init) - flowCharacteristic(0)Used for simplified initialization model
IntegernParallel1Number of pumps in parallel
AngularVelocity_rpmN_nominal Nominal rotational speed for flow characteristic
Densityrho_nominalMedium.density_pTX(Medium.p_default, Medium.T_default, Medium.X_default)Nominal fluid density for characteristic
Booleanuse_powerCharacteristicfalseUse powerCharacteristic (vs. efficiencyCharacteristic)
BooleancheckValvefalse= true to prevent reverse flow
VolumeV0Volume inside the pump
DynamicsenergyDynamicsTypes.​Dynamics.​SteadyStateFormulation of energy balance
DynamicsmassDynamicsTypes.​Dynamics.​SteadyStateFormulation of mass balance
final DynamicssubstanceDynamicsmassDynamicsFormulation of substance balance
final DynamicstraceDynamicsmassDynamicsFormulation of trace substance balance
final AbsolutePressurep_startp_b_startStart value of pressure
Booleanuse_T_starttrue= true, use T_start, otherwise h_start
TemperatureT_startif use_T_start then system.T_start else Medium.temperature_phX(p_start, h_start, X_start)Start value of temperature
SpecificEnthalpyh_startif use_T_start then Medium.specificEnthalpy_pTX(p_start, T_start, X_start) else Medium.h_defaultStart value of specific enthalpy
MassFractionX_start[Medium.nX]Medium.​X_defaultStart value of mass fractions m_i/m
ExtraPropertyC_start[Medium.nC]Medium.​C_defaultStart value of trace substances
Booleanuse_HeatTransferfalse= true to use a HeatTransfer model, e.g., for a housing
final Accelerationgsystem.​g 
final Booleanshow_NPSHafalseobsolete -- remove modifier and specify Monitoring for NPSH instead

Connectors

TypeNameDescription
FluidPort_aport_aFluid connector a (positive design flow direction is from port_a to port_b)
FluidPort_bport_bFluid connector b (positive design flow direction is from port_a to port_b)
HeatPort_aheatPort 
Flange_ashaft 

Model Modelica.​Fluid.​Machines.​ControlledPump
Centrifugal pump with ideally controlled mass flow rate

Information

This model describes a centrifugal pump (or a group of nParallel pumps) with ideally controlled mass flow rate or pressure.

Nominal values are used to predefine an exemplary pump characteristics and to define the operation of the pump. The input connectors m_flow_set or p_set can optionally be enabled to provide time varying set points.

Use this model if the pump characteristics is of secondary interest. The actual characteristics can be configured later on for the appropriate rotational speed N. Then the model can be replaced with a Pump with rotational shaft or with a PrescribedPump.

Extends from Modelica.​Fluid.​Machines.​BaseClasses.​PartialPump (Base model for centrifugal pumps).

Parameters

TypeNameDefaultDescription
BooleanallowFlowReversalsystem.​allowFlowReversal= true to allow flow reversal, false restricts to design direction (port_a -> port_b)
AbsolutePressurep_a_startsystem.​p_startGuess value for inlet pressure
AbsolutePressurep_b_startp_a_startGuess value for outlet pressure
MassFlowRatem_flow_startsystem.​m_flow_startGuess value of m_flow = port_a.m_flow
final VolumeFlowRateV_flow_single_initm_flow_start / rho_nominal / nParallelUsed for simplified initialization model
final Heightdelta_head_initflowCharacteristic(V_flow_single_init) - flowCharacteristic(0)Used for simplified initialization model
IntegernParallel1Number of pumps in parallel
AngularVelocity_rpmN_nominal1500Nominal rotational speed for flow characteristic
Densityrho_nominalMedium.density_pTX(Medium.p_default, Medium.T_default, Medium.X_default)Nominal fluid density for characteristic
Booleanuse_powerCharacteristicfalseUse powerCharacteristic (vs. efficiencyCharacteristic)
BooleancheckValvefalse= true to prevent reverse flow
VolumeV0Volume inside the pump
DynamicsenergyDynamicsTypes.​Dynamics.​SteadyStateFormulation of energy balance
DynamicsmassDynamicsTypes.​Dynamics.​SteadyStateFormulation of mass balance
final DynamicssubstanceDynamicsmassDynamicsFormulation of substance balance
final DynamicstraceDynamicsmassDynamicsFormulation of trace substance balance
final AbsolutePressurep_startp_b_startStart value of pressure
Booleanuse_T_starttrue= true, use T_start, otherwise h_start
TemperatureT_startif use_T_start then system.T_start else Medium.temperature_phX(p_start, h_start, X_start)Start value of temperature
SpecificEnthalpyh_startif use_T_start then Medium.specificEnthalpy_pTX(p_start, T_start, X_start) else Medium.h_defaultStart value of specific enthalpy
MassFractionX_start[Medium.nX]Medium.​X_defaultStart value of mass fractions m_i/m
ExtraPropertyC_start[Medium.nC]Medium.​C_defaultStart value of trace substances
Booleanuse_HeatTransferfalse= true to use a HeatTransfer model, e.g., for a housing
final Accelerationgsystem.​g 
final Booleanshow_NPSHafalseobsolete -- remove modifier and specify Monitoring for NPSH instead
AbsolutePressurep_a_nominal Nominal inlet pressure for predefined pump characteristics
AbsolutePressurep_b_nominal Nominal outlet pressure, fixed if not control_m_flow and not use_p_set
MassFlowRatem_flow_nominal Nominal mass flow rate, fixed if control_m_flow and not use_m_flow_set
Booleancontrol_m_flowtrue= false to control outlet pressure port_b.p instead of m_flow
Booleanuse_m_flow_setfalse= true to use input signal m_flow_set instead of m_flow_nominal
Booleanuse_p_setfalse= true to use input signal p_set instead of p_b_nominal
final VolumeFlowRateV_flow_opm_flow_nominal / rho_nominaloperational volume flow rate according to nominal values
final Heighthead_op(p_b_nominal - p_a_nominal) / (rho_nominal * g)operational pump head according to nominal values

Connectors

TypeNameDescription
FluidPort_aport_aFluid connector a (positive design flow direction is from port_a to port_b)
FluidPort_bport_bFluid connector b (positive design flow direction is from port_a to port_b)
HeatPort_aheatPort 
input RealInputm_flow_setPrescribed mass flow rate
input RealInputp_setPrescribed outlet pressure

Model Modelica.​Fluid.​Machines.​PrescribedPump
Centrifugal pump with ideally controlled speed

Information

This model describes a centrifugal pump (or a group of nParallel pumps) with prescribed speed, either fixed or provided by an external signal.

The model extends PartialPump

If the N_in input connector is wired, it provides rotational speed of the pumps (rpm); otherwise, a constant rotational speed equal to n_const (which can be different from N_nominal) is assumed.

Extends from Modelica.​Fluid.​Machines.​BaseClasses.​PartialPump (Base model for centrifugal pumps).

Parameters

TypeNameDefaultDescription
BooleanallowFlowReversalsystem.​allowFlowReversal= true to allow flow reversal, false restricts to design direction (port_a -> port_b)
AbsolutePressurep_a_startsystem.​p_startGuess value for inlet pressure
AbsolutePressurep_b_startp_a_startGuess value for outlet pressure
MassFlowRatem_flow_startsystem.​m_flow_startGuess value of m_flow = port_a.m_flow
final VolumeFlowRateV_flow_single_initm_flow_start / rho_nominal / nParallelUsed for simplified initialization model
final Heightdelta_head_initflowCharacteristic(V_flow_single_init) - flowCharacteristic(0)Used for simplified initialization model
IntegernParallel1Number of pumps in parallel
AngularVelocity_rpmN_nominal Nominal rotational speed for flow characteristic
Densityrho_nominalMedium.density_pTX(Medium.p_default, Medium.T_default, Medium.X_default)Nominal fluid density for characteristic
Booleanuse_powerCharacteristicfalseUse powerCharacteristic (vs. efficiencyCharacteristic)
BooleancheckValvefalse= true to prevent reverse flow
VolumeV0Volume inside the pump
DynamicsenergyDynamicsTypes.​Dynamics.​SteadyStateFormulation of energy balance
DynamicsmassDynamicsTypes.​Dynamics.​SteadyStateFormulation of mass balance
final DynamicssubstanceDynamicsmassDynamicsFormulation of substance balance
final DynamicstraceDynamicsmassDynamicsFormulation of trace substance balance
final AbsolutePressurep_startp_b_startStart value of pressure
Booleanuse_T_starttrue= true, use T_start, otherwise h_start
TemperatureT_startif use_T_start then system.T_start else Medium.temperature_phX(p_start, h_start, X_start)Start value of temperature
SpecificEnthalpyh_startif use_T_start then Medium.specificEnthalpy_pTX(p_start, T_start, X_start) else Medium.h_defaultStart value of specific enthalpy
MassFractionX_start[Medium.nX]Medium.​X_defaultStart value of mass fractions m_i/m
ExtraPropertyC_start[Medium.nC]Medium.​C_defaultStart value of trace substances
Booleanuse_HeatTransferfalse= true to use a HeatTransfer model, e.g., for a housing
final Accelerationgsystem.​g 
final Booleanshow_NPSHafalseobsolete -- remove modifier and specify Monitoring for NPSH instead
Booleanuse_N_infalseGet the rotational speed from the input connector
AngularVelocity_rpmN_constN_nominalConstant rotational speed

Connectors

TypeNameDescription
FluidPort_aport_aFluid connector a (positive design flow direction is from port_a to port_b)
FluidPort_bport_bFluid connector b (positive design flow direction is from port_a to port_b)
HeatPort_aheatPort 
input RealInputN_inPrescribed rotational speed

Generated 2018-12-12 12:13:24 EST by MapleSim.