Buildings.Fluid.Movers.Examples.BaseClasses

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Buildings.Fluid.Movers.Examples.BaseClasses

Package with base classes for Buildings.Fluid.Movers.Examples

Information

This package contains base classes that are used to construct the models in Buildings.Fluid.Movers.Examples.

Extends from Modelica.Icons.BasesPackage (Icon for packages containing base classes).

Package Content

Name	Description
FlowMachine_ZeroFlow	Base class to test flow machines with zero flow rate
ControlledFlowMachine

Buildings.Fluid.Movers.Examples.BaseClasses.FlowMachine_ZeroFlow

Base class to test flow machines with zero flow rate

Information

This example demonstrates the use of a flow machine whose flow rate transitions to zero.

Parameters

Type Name Default Description

MassFlowRate m_flow_nominal 1 Nominal mass flow rate [kg/s]

Pressure dp_nominal 500 Nominal pressure difference [Pa]

PartialFlowMachine floMacSta redeclare Buildings.Fluid.Mo... Static model of a flow machine

PartialFlowMachine floMacDyn redeclare Buildings.Fluid.Mo... Dynamic model of a flow machine

Type	Name	Default	Description
MassFlowRate	m_flow_nominal	1	Nominal mass flow rate [kg/s]
Pressure	dp_nominal	500	Nominal pressure difference [Pa]
PartialFlowMachine	floMacSta	redeclare Buildings.Fluid.Mo...	Static model of a flow machine
PartialFlowMachine	floMacDyn	redeclare Buildings.Fluid.Mo...	Dynamic model of a flow machine

Modelica definition

partial model FlowMachine_ZeroFlow 
  "Base class to test flow machines with zero flow rate"

  package Medium = Buildings.Media.GasesPTDecoupled.MoistAirUnsaturated;

  inner Modelica.Fluid.System system;

  parameter Modelica.SIunits.MassFlowRate m_flow_nominal= 1 
    "Nominal mass flow rate";
  parameter Modelica.SIunits.Pressure dp_nominal = 500 
    "Nominal pressure difference";

  Modelica.Blocks.Sources.Ramp y(
    offset=1,
    duration=0.5,
    startTime=0.25,
    height=-1) "Input signal";
  Buildings.Fluid.Sources.Boundary_pT sou(
    redeclare package Medium = Medium,
    use_p_in=false,
    p=system.p_ambient,
    T=293.15,
    nPorts=4);
  Buildings.Fluid.FixedResistances.FixedResistanceDpM dpSta(
    redeclare package Medium = Medium,
    m_flow_nominal=m_flow_nominal,
    dp_nominal=dp_nominal/2) "Pressure drop";
  replaceable Buildings.Fluid.Movers.BaseClasses.PartialFlowMachine floMacSta(
    redeclare package Medium = Medium,
    energyDynamics=Modelica.Fluid.Types.Dynamics.SteadyState,
    dynamicBalance=false)
                      constrainedby 
    Buildings.Fluid.Movers.BaseClasses.PartialFlowMachine 
    "Static model of a flow machine";
  replaceable Buildings.Fluid.Movers.BaseClasses.PartialFlowMachine floMacDyn(
    redeclare package Medium = Medium,
    energyDynamics=Modelica.Fluid.Types.Dynamics.DynamicFreeInitial)
                      constrainedby 
    Buildings.Fluid.Movers.BaseClasses.PartialFlowMachine 
    "Dynamic model of a flow machine";
  Buildings.Fluid.FixedResistances.FixedResistanceDpM dpDyn(
    redeclare package Medium = Medium,
    m_flow_nominal=m_flow_nominal,
    dp_nominal=dp_nominal/2) "Pressure drop";
  Modelica.Blocks.Math.Gain gain "Gain for input signal";
  Buildings.Fluid.FixedResistances.FixedResistanceDpM dpSta1(
    redeclare package Medium = Medium,
    m_flow_nominal=m_flow_nominal,
    dp_nominal=dp_nominal/2) "Pressure drop";
  Buildings.Fluid.FixedResistances.FixedResistanceDpM dpDyn1(
    redeclare package Medium = Medium,
    m_flow_nominal=m_flow_nominal,
    dp_nominal=dp_nominal/2) "Pressure drop";
equation 
  connect(floMacSta.port_b, dpSta.port_a);
  connect(y.y, gain.u);
  connect(floMacDyn.port_b, dpDyn.port_a);
  connect(dpSta1.port_b, floMacSta.port_a);
  connect(dpDyn1.port_b, floMacDyn.port_a);
  connect(dpSta1.port_a, sou.ports[1]);
  connect(dpDyn1.port_a, sou.ports[2]);
  connect(dpDyn.port_b, sou.ports[3]);
  connect(dpSta.port_b, sou.ports[4]);
end FlowMachine_ZeroFlow;

Buildings.Fluid.Movers.Examples.BaseClasses.ControlledFlowMachine

Information

This example demonstrates the use of the flow model with four different configuration. At steady-state, all flow models have the same mass flow rate and pressure difference.

Modelica definition

model ControlledFlowMachine

  package Medium = Buildings.Media.IdealGases.SimpleAir;

  Modelica.Blocks.Sources.Pulse     y(
    startTime=0,
    offset=0,
    amplitude=1,
    period=120,
    width=50);
  Buildings.Fluid.Sources.Boundary_pT sou(
    redeclare package Medium = Medium,
    use_p_in=false,
    p=system.p_ambient,
    T=293.15,
    nPorts=4);
  inner Modelica.Fluid.System system;
  Buildings.Fluid.Sensors.MassFlowRate masFloRat1(redeclare package Medium =
        Medium);
  Buildings.Fluid.Sensors.RelativePressure relPre(redeclare package Medium =
        Medium);
  Buildings.Fluid.Movers.FlowMachine_y fan1(
    redeclare package Medium = Medium,
    pressure(final V_flow={0,1.8,3}, dp={1000,600,0}),
    dynamicBalance=false);
  FixedResistances.FixedResistanceDpM dp1(
    m_flow_nominal=6000/3600*1.2,
    redeclare package Medium = Medium,
    dp_nominal=300) "Pressure drop";
  FixedResistances.FixedResistanceDpM dp2(
    m_flow_nominal=6000/3600*1.2,
    redeclare package Medium = Medium,
    dp_nominal=300) "Pressure drop";
  Buildings.Fluid.Sensors.MassFlowRate masFloRat2(redeclare package Medium =
        Medium);
  FixedResistances.FixedResistanceDpM dp3(
    m_flow_nominal=6000/3600*1.2,
    redeclare package Medium = Medium,
    dp_nominal=300) "Pressure drop";
  Buildings.Fluid.Sensors.MassFlowRate masFloRat3(redeclare package Medium =
        Medium);
  Buildings.Fluid.Movers.FlowMachine_dp fan3(
    redeclare package Medium = Medium,
    m_flow_nominal=6000/3600*1.2,
    dynamicBalance=false);
  Buildings.Fluid.Movers.FlowMachine_m_flow fan2(
    redeclare package Medium = Medium,
    m_flow_nominal=6000/3600*1.2,
    dynamicBalance=false);
  FixedResistances.FixedResistanceDpM dp4(
    m_flow_nominal=6000/3600*1.2,
    redeclare package Medium = Medium,
    dp_nominal=300) "Pressure drop";
  Buildings.Fluid.Sensors.MassFlowRate masFloRat4(redeclare package Medium =
        Medium);
  Buildings.Fluid.Movers.FlowMachine_Nrpm fan4(
    redeclare package Medium = Medium,
    pressure(final V_flow={0,1.8,3}, dp={1000,600,0}),
    dynamicBalance=false);
  Modelica.Blocks.Math.Gain gain(k=1500) "Converts y to nominal rpm";
  FixedResistances.FixedResistanceDpM dp5(
    m_flow_nominal=6000/3600*1.2,
    redeclare package Medium = Medium,
    dp_nominal=300) "Pressure drop";
  FixedResistances.FixedResistanceDpM dp6(
    m_flow_nominal=6000/3600*1.2,
    redeclare package Medium = Medium,
    dp_nominal=300) "Pressure drop";
  FixedResistances.FixedResistanceDpM dp7(
    m_flow_nominal=6000/3600*1.2,
    redeclare package Medium = Medium,
    dp_nominal=300) "Pressure drop";
  FixedResistances.FixedResistanceDpM dp8(
    m_flow_nominal=6000/3600*1.2,
    redeclare package Medium = Medium,
    dp_nominal=300) "Pressure drop";
  Buildings.Fluid.Sources.Boundary_pT sin(
    redeclare package Medium = Medium,
    use_p_in=false,
    p=system.p_ambient,
    T=293.15,
    nPorts=4);
equation 

  connect(fan1.port_a, relPre.port_b);
  connect(fan1.port_b, relPre.port_a);
  connect(fan1.port_b, dp1.port_a);
  connect(fan2.port_b, dp2.port_a);
  connect(fan3.port_b, dp3.port_a);
  connect(fan4.port_b, dp4.port_a);
  connect(gain.y, fan4.Nrpm);
  connect(masFloRat1.m_flow, fan2.m_flow_in);
  connect(relPre.p_rel, fan3.dp_in);
  connect(dp8.port_b, fan4.port_a);
  connect(dp5.port_b, fan1.port_a);
  connect(dp6.port_b, fan2.port_a);
  connect(dp7.port_b, fan3.port_a);
  connect(y.y, fan1.y);
  connect(y.y, gain.u);
  connect(dp8.port_a, sou.ports[1]);
  connect(dp5.port_a, sou.ports[2]);
  connect(dp6.port_a, sou.ports[3]);
  connect(dp7.port_a, sou.ports[4]);
  connect(dp4.port_b, masFloRat4.port_a);
  connect(dp1.port_b, masFloRat1.port_a);
  connect(dp2.port_b, masFloRat2.port_a);
  connect(dp3.port_b, masFloRat3.port_a);
  connect(masFloRat4.port_b, sin.ports[1]);
  connect(masFloRat1.port_b, sin.ports[2]);
  connect(masFloRat2.port_b, sin.ports[3]);
  connect(masFloRat3.port_b, sin.ports[4]);
end ControlledFlowMachine;

Automatically generated Thu Oct 24 15:09:46 2013.