Buildings.Fluids.FixedResistances.Examples

Information

Extends from Buildings.BaseClasses.BaseIconExamples (Icon for Examples packages).

Package Content

Name	Description
FixedResistance
FixedResistancesParallel
Resistances	Test of multiple resistances
SplitterFixedResistanceDpM

Buildings.Fluids.FixedResistances.Examples.FixedResistance

Modelica definition

model FixedResistance
  import Buildings;

 package Medium = 
        Buildings.Media.ConstantPropertyLiquidWater;
    Modelica.Blocks.Sources.Constant PAtm(k=101325);
    Modelica.Blocks.Sources.Ramp P(
      duration=1,
    height=20,
    offset=101315);
    Buildings.Fluids.FixedResistances.FixedResistanceDpM res1(
    redeclare package Medium = Medium,
    from_dp=true,
    m0_flow=5,
    dp0=10);
  Modelica_Fluid.Sources.Boundary_pT sou1(          redeclare package Medium = 
        Medium,
    use_p_in=true,
    T=293.15,
    nPorts=3);
  Modelica_Fluid.Sources.Boundary_pT sin1(          redeclare package Medium = 
        Medium, T=283.15,
    use_p_in=true,
    nPorts=3);
    Buildings.Fluids.FixedResistances.FixedResistanceDpM res2(
    redeclare package Medium = Medium,
    from_dp=true,
    m0_flow=5,
    dp0=10,
    use_dh=true);
    Buildings.Fluids.FixedResistances.FixedResistanceDpM res3(
    redeclare package Medium = Medium,
    from_dp=true,
    m0_flow=5,
    dp0=10,
    use_dh=true);
  FixedResistances.LosslessPipe pipCon(redeclare package Medium = Medium) 
    "Lossless pipe connection";
  Modelica_Fluid.Sensors.MassFlowRate masFlo2(redeclare package Medium = Medium) 
    "Mass flow rate sensor";
  Modelica_Fluid.Sensors.MassFlowRate masFlo3(redeclare package Medium = Medium) 
    "Mass flow rate sensor";
  Buildings.Utilities.Diagnostics.AssertEquality assEqu(threShold=1E-4, message=
        "Inputs differ, check that lossless pipe is correctly implemented.") 
    "Assert equality of the two mass flow rates";
  inner Modelica_Fluid.System system;
equation 
  connect(res2.port_b, masFlo2.port_a);
  connect(res3.port_b, masFlo3.port_a);
  connect(masFlo3.port_b, pipCon.port_a);
  connect(P.y, sou1.p_in);
  connect(sou1.ports[1], res1.port_a);
  connect(sin1.ports[1], res1.port_b);
  connect(masFlo3.m_flow, assEqu.u1);
  connect(masFlo2.m_flow, assEqu.u2);
  connect(PAtm.y, sin1.p_in);
  connect(sou1.ports[2], res2.port_a);
  connect(sou1.ports[3], res3.port_a);
  connect(sin1.ports[2], masFlo2.port_b);
  connect(sin1.ports[3], pipCon.port_b);
end FixedResistance;

Buildings.Fluids.FixedResistances.Examples.FixedResistancesParallel

Modelica definition

model FixedResistancesParallel
  import Buildings;

 package Medium = 
        Buildings.Media.ConstantPropertyLiquidWater;
    Modelica.Blocks.Sources.Constant PAtm(k=101325);
    Modelica.Blocks.Sources.Ramp P(
      duration=1,
    height=20,
    offset=101315);
    Buildings.Fluids.FixedResistances.FixedResistanceDpM res1(
    redeclare package Medium = Medium,
    m0_flow=5,
    dp0=10,
    deltaM=0.3,
    linearized=false,
    from_dp=false);
  Modelica_Fluid.Sources.Boundary_pT sou1(          redeclare package Medium = 
        Medium,
    T=293.15,
    nPorts=2,
    use_p_in=true);
  Modelica_Fluid.Sources.Boundary_pT sin1(          redeclare package Medium = 
        Medium,
    T=283.15,
    nPorts=2,
    use_p_in=true);
    Buildings.Fluids.FixedResistances.FixedResistanceDpM res2(
    redeclare package Medium = Medium,
    m0_flow=5,
    dp0=10,
    deltaM=0.3,
    linearized=false,
    from_dp=false);
  Modelica_Fluid.Sensors.MassFlowRate masFlo2(redeclare package Medium = Medium) 
    "Mass flow rate sensor";
  Buildings.Utilities.Diagnostics.AssertEquality assEqu(threShold=1E-4, message=
        "Inputs differ, check that lossless pipe is correctly implemented.") 
    "Assert equality of the two mass flow rates";
  Modelica_Fluid.Sensors.MassFlowRate masFlo1(redeclare package Medium = Medium) 
    "Mass flow rate sensor";
  inner Modelica_Fluid.System system(p_ambient=101325);
equation 
  connect(PAtm.y, sin1.p_in);
  connect(P.y, sou1.p_in);
  connect(res2.port_b, masFlo2.port_a);
  connect(res1.port_b, masFlo1.port_a);
  connect(sou1.ports[1], res1.port_a);
  connect(sou1.ports[2], res2.port_a);
  connect(sin1.ports[1], masFlo1.port_b);
  connect(sin1.ports[2], masFlo2.port_b);
  connect(masFlo2.m_flow, assEqu.u1);
  connect(masFlo1.m_flow, assEqu.u2);
end FixedResistancesParallel;

Buildings.Fluids.FixedResistances.Examples.Resistances

Parameters

Type	Name	Default	Description
Pressure	dp0	5	Nominal pressure drop for each resistance [Pa]
Integer	nRes	3	Number of resistances

Modelica definition

model Resistances "Test of multiple resistances"
 package Medium = Modelica.Media.Air.SimpleAir;

    Modelica.Blocks.Sources.Constant PAtm(k=101325);
   parameter Modelica.SIunits.Pressure dp0 = 5 
    "Nominal pressure drop for each resistance";
    Modelica.Blocks.Sources.Ramp P(
      duration=1,
    height=2*dp0*nRes,
    offset=101325 - dp0*nRes);
  Modelica_Fluid.Sources.Boundary_pT sou(             redeclare package Medium
      =        Medium, T=273.15 + 20,
    use_p_in=true,
    nPorts=1);
  Modelica_Fluid.Sources.Boundary_pT sin(             redeclare package Medium
      =        Medium, T=273.15 + 10,
    use_p_in=true,
    nPorts=1);
  parameter Integer nRes( min=2) = 3 "Number of resistances";
    Buildings.Fluids.FixedResistances.FixedResistanceDpM[
                       nRes] res(
    redeclare each package Medium = Medium,
    each dp0=dp0,
    each from_dp = false,
    each m0_flow=2);
  inner Modelica_Fluid.System system(p_ambient=101325);
equation 
  for i in 1:nRes-1 loop
  connect(res[i].port_b, res[i+1].port_a);
  end for;
  connect(PAtm.y, sin.p_in);
  connect(P.y, sou.p_in);
  connect(sin.ports[1], res[nRes].port_b);
  connect(sou.ports[1], res[1].port_a);
end Resistances;

Buildings.Fluids.FixedResistances.Examples.SplitterFixedResistanceDpM

Modelica definition

model SplitterFixedResistanceDpM


 package Medium = Modelica.Media.Air.SimpleAir;

  Buildings.Fluids.FixedResistances.SplitterFixedResistanceDpM spl(
    m0_flow={1,2,3},
    dp0={5,10,15},
    dh={1,2,3},
    redeclare package Medium = Medium) "Splitter";
  Modelica_Fluid.Sources.Boundary_pT bou1(             redeclare package Medium
      =        Medium, T=273.15 + 10,
    use_p_in=true,
    nPorts=1);
  Modelica_Fluid.Sources.Boundary_pT bou2(             redeclare package Medium
      =        Medium, T=273.15 + 20,
    use_p_in=true,
    nPorts=1);
  Modelica_Fluid.Sources.Boundary_pT bou3(             redeclare package Medium
      =        Medium, T=273.15 + 30,
    use_p_in=true,
    nPorts=1);
    Modelica.Blocks.Sources.Constant P2(k=101325);
    Modelica.Blocks.Sources.Ramp P1(
    offset=101320,
    height=10,
    duration=0.5);
    Modelica.Blocks.Sources.Ramp P3(
      offset=101320,
      height=10,
    duration=0.5,
    startTime=0.5);
  inner Modelica_Fluid.System system(p_ambient=101325);
equation 
  connect(P1.y, bou1.p_in);
  connect(P2.y, bou2.p_in);
  connect(bou3.p_in, P3.y);
  connect(bou1.ports[1], spl.port_1);
  connect(bou3.ports[1], spl.port_3);
  connect(spl.port_2, bou2.ports[1]);
end SplitterFixedResistanceDpM;