WOLFRAM SYSTEMMODELER

ControlledPump

Centrifugal pump with ideally controlled mass flow rate

Diagram

Wolfram Language

In[1]:=
SystemModel["Modelica.Fluid.Machines.ControlledPump"]
Out[1]:=

Information

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

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.

Parameters (33)

allowFlowReversal

Value: system.allowFlowReversal

Type: Boolean

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

energyDynamics

Value: Types.Dynamics.SteadyState

Type: Dynamics

Description: Formulation of energy balance

massDynamics

Value: Types.Dynamics.SteadyState

Type: Dynamics

Description: Formulation of mass balance

substanceDynamics

Value: massDynamics

Type: Dynamics

Description: Formulation of substance balance

traceDynamics

Value: massDynamics

Type: Dynamics

Description: Formulation of trace substance balance

p_start

Value: p_b_start

Type: AbsolutePressure (Pa)

Description: Start value of pressure

use_T_start

Value: true

Type: Boolean

Description: = true, use T_start, otherwise h_start

T_start

Value: if use_T_start then system.T_start else Medium.temperature_phX(p_start, h_start, X_start)

Type: Temperature (K)

Description: Start value of temperature

h_start

Value: if use_T_start then Medium.specificEnthalpy_pTX(p_start, 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

p_a_start

Value: system.p_start

Type: AbsolutePressure (Pa)

Description: Guess value for inlet pressure

p_b_start

Value: p_a_start

Type: AbsolutePressure (Pa)

Description: Guess value for outlet pressure

m_flow_start

Value: system.m_flow_start

Type: MassFlowRate (kg/s)

Description: Guess value of m_flow = port_a.m_flow

V_flow_single_init

Value: m_flow_start / rho_nominal / nParallel

Type: VolumeFlowRate (m³/s)

Description: Used for simplified initialization model

delta_head_init

Value: flowCharacteristic(V_flow_single_init * 1.1) - flowCharacteristic(V_flow_single_init)

Type: Position (m)

Description: Delta head for a 10% increase of flow at the initialization point

nParallel

Value: 1

Type: Integer

Description: Number of pumps in parallel

N_nominal

Value: 1500

Type: AngularVelocity_rpm (rev/min)

Description: Nominal rotational speed for flow characteristic

rho_nominal

Value: Medium.density_pTX(Medium.p_default, Medium.T_default, Medium.X_default)

Type: Density (kg/m³)

Description: Nominal fluid density for characteristic

use_powerCharacteristic

Value: false

Type: Boolean

Description: Use powerCharacteristic (vs. efficiencyCharacteristic)

checkValve

Value: false

Type: Boolean

Description: = true to prevent reverse flow

V

Value: 0

Type: Volume (m³)

Description: Volume inside the pump

use_HeatTransfer

Value: false

Type: Boolean

Description: = true to use a HeatTransfer model, e.g., for a housing

g

Value: system.g

Type: Acceleration (m/s²)

show_NPSHa

Value: false

Type: Boolean

Description: obsolete -- remove modifier and specify Monitoring for NPSH instead

p_a_nominal

Value:

Type: AbsolutePressure (Pa)

Description: Nominal inlet pressure for predefined pump characteristics

p_b_nominal

Value:

Type: AbsolutePressure (Pa)

Description: Nominal outlet pressure, fixed if not control_m_flow and not use_p_set

m_flow_nominal

Value:

Type: MassFlowRate (kg/s)

Description: Nominal mass flow rate, fixed if control_m_flow and not use_m_flow_set

control_m_flow

Value: true

Type: Boolean

Description: = false to control outlet pressure port_b.p instead of m_flow

use_m_flow_set

Value: false

Type: Boolean

Description: = true to use input signal m_flow_set instead of m_flow_nominal

use_p_set

Value: false

Type: Boolean

Description: = true to use input signal p_set instead of p_b_nominal

V_flow_op

Value: m_flow_nominal / rho_nominal

Type: VolumeFlowRate (m³/s)

Description: operational volume flow rate according to nominal values

head_op

Value: (p_b_nominal - p_a_nominal) / (rho_nominal * g)

Type: Position (m)

Description: operational pump head according to nominal values

Inputs (1)

fluidVolume

Default Value: V

Type: Volume (m³)

Description: Volume

Connectors (5)

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)

heatPort

Type: HeatPort_a

m_flow_set

Type: RealInput

Description: Prescribed mass flow rate

p_set

Type: RealInput

Description: Prescribed outlet pressure

Components (4)

system

Type: System

Description: System properties

medium

Type: BaseProperties

heatTransfer

Type: HeatTransfer

monitoring

Type: Monitoring

Description: Monitoring model

Used in Examples (2)

HeatingSystem

Modelica.Fluid.Examples

Simple model of a heating system

InverseParameterization

Modelica.Fluid.Examples

Demonstrates the parameterization of a pump and a pipe for given nominal values