modelPipeFlow2Ph

Single pipe(not double) for two phases flow. With no detailed heat transfer model. Muller-Steinhagen and Heck method

Extends from FreeFluids.Pipes.PipeFlowBase (Base model for a single medium pipe.).

Information

It is the extension of the PipeflowBase model for two phase flow. The friction loss is calculated according to Muller-Steinhagen and Heck methodology.

Parameters

TypeNameDefaultDescription
Physical data
BooleanuseTubeLength (from PipePhysical)trueuse the supplied length
Modelica.Units.SI.DistancelTube (from PipePhysical)0supplied individual tube length
BooleanfixNumTubes (from PipePhysical)trueif true fixes the number of tubes to numTubes
IntegernumTubes (from PipePhysical)1number of parallel identical paths
BooleanisCircular (from PipePhysical)truethe pipe is circular in shape
BooleanuseDiameter (from PipePhysical)truethe supplied diameter will be used for calculation of section and perimeter
Modelica.Units.SI.Distancedi (from PipePhysical)0.0supplied internal diameter if path is circular
BooleanuseSectionAndPerimeter (from PipePhysical)falsethe supplied section and perimeter will be used
Modelica.Units.SI.Areasection (from PipePhysical)0supplied pipe section if not circular
Modelica.Units.SI.Distanceperimeter (from PipePhysical)0supplied perimeter if not circular
Modelica.Units.SI.Distancethickness (from PipePhysical)1e-3pipe thickness. Vessel wall thickness for halfcoils
Modelica.Units.SI.Distanceroughness (from PipePhysical)1.5e-005pipe roughness. SS:1.5e-5, Steel new:4.6e-5, Steel old:2.0e-4, Concrete:1.5e-3
Modelica.Units.SI.DistancethicknessInsul (from PipePhysical)0insulation thickness
Modelica.Units.SI.DensityrhoWall (from PipePhysical)8000
Ports links
BooleanuseElevDifference (from TwoFluidPorts)trueintroduces, or not, an equation for the ports elevation. Use only in one connector
FreeFluids.Types.ElevationOptionelevCalcMethod (from TwoFluidPorts)FreeFluids.Types.ElevationOption.differentialif useElevDifference==true, selects the equation to use: differential, or absolute for PortB
Modelica.Units.SI.LengthelevDifference (from TwoFluidPorts)0.0used only if previously selected. Positive if PortB higher than PortA
Modelica.Units.SI.LengthportBelevation (from TwoFluidPorts)0.0used only if previously selected.
BooleancalcEnthalpyDifference (from TwoFluidPorts)trueif true, will calculate the enthalpy difference between ports. Use only in one connector
BooleanpassComposition (from TwoFluidPorts)trueif true, the equation PortA.X=PortB.X will be activated
Flow
IntegernumActiveTubes (from Pipe)numTubesnumber of parallel identical paths used with flow. Default=numTubes
RealpipeComplexity (from Pipe)0Approx. estimation of equivalent length,0=not used,0.25=supply lines,0.5=long runs, 1=normal,2=valves,4=complex valves
RealequivL_Di (from Pipe)0Equivalent length of accesories as multiples of Di
RealnumVelocityHeads (from Pipe)0number of velocity heads for pressure loss
Modelica.Units.SI.Areakv (from Pipe)0This allows for special head loses to be incorporated inside the pipe calculation via Kv
Fractionaperture (from Pipe)1Fraction of Kv used
BooleanfullBore (from Pipe)truetrue if the full pipe section is used for flow
BooleanisCompressibleFlow (from Pipe)falseindicates if kinetic energy and momentum are taken into account or not
BooleantwoPhaseFlow (from PipeFlowBase)falseindicates if there is a two phase flow
Heat transfer
FreeFluids.Types.ThermalTypethermalType (from PipeFlowBase)FreeFluids.Types.ThermalType.detailedAlternatives: detailed, isenthalpic, adiabatic, isothermal, fixed W, fixed deltaT. If detailed, W calculation must be supplied
Modelica.Units.SI.HeatFlowRatefixedW (from PipeFlowBase)0Heat exchange if thermaltype = fixedPower. Positive if heat enters the tube
Modelica.Units.SI.TemperatureDifferencefixedDeltaT (from PipeFlowBase)0fixed T diff. between ports if thermalType = fixedDeltaT. Positive if Tb > Ta
Optional user phys. prop.
Modelica.Units.SI.DensityrhoL0fixed liquid density to use in calculations. If 0, will be calculated from the medium
Modelica.Units.SI.DynamicViscositymuL0fixed liquid dynamic viscosity to use in calculations
Modelica.Units.SI.DensityrhoG0fixed gas density to use in calculations
Modelica.Units.SI.DynamicViscositymuG0fixed gas dynamic viscosity to use in calculations
Realx0fixed mass gas fraction at average conditions

Connectors

TypeNameDefaultDescription
FreeFluids.Interfaces.FluidPortAPortA (from TwoFluidPorts)
FreeFluids.Interfaces.FluidPortBPortB (from TwoFluidPorts)

Components

TypeNameDefaultDescription
Modelica.Units.SI.DiameterDi (from PipePhysical)pipe internal diameter only if circular, otherwise four times Section/Perimeter
Modelica.Units.SI.AreaPathSection (from PipePhysical)Internal section of the tube. But not the flow section if double pipe
Modelica.Units.SI.DistancePathPerimeter (from PipePhysical)Internal perimeter of the tube. But not the flow perimeter if double pipe
Modelica.Units.SI.DistanceLtotal (from PipePhysical)total pipe length, as necessary for obtainning its total weight
Modelica.Units.SI.DistanceLtube (from PipePhysical)pipe path length, as necessary for obtainning friction loss
IntegerNumTubes (from PipePhysical)number of parallel identical paths
Modelica.Units.SI.AreaSiTube (from PipePhysical)each tube internal surface
Modelica.Units.SI.AreaSiTotal (from PipePhysical)total pipe internal surface
Modelica.Units.SI.VolumeViTube (from PipePhysical)each tube internal volume
Modelica.Units.SI.VolumeViTotal (from PipePhysical)total pipe internal volume
Modelica.Units.SI.DiameterDo (from PipePhysical)pipe external diameter
Modelica.Units.SI.DiameterDinsul (from PipePhysical)pipe diameter with insulation
Modelica.Units.SI.AreaSoTube (from PipePhysical)each tube external surface
Modelica.Units.SI.AreaSoTotal (from PipePhysical)total pipe external surface
Modelica.Units.SI.VolumeVoTube (from PipePhysical)each tube external volume
Modelica.Units.SI.VolumeVoTotal (from PipePhysical)total pipe external volume
Modelica.Units.SI.AreaSinsulTube (from PipePhysical)each tube insulation surface
Modelica.Units.SI.AreaSinsulTotal (from PipePhysical)total pipe insulation surface
Modelica.Units.SI.MassMassPipeTotal (from PipePhysical)total mass of the pipe
Modelica.Units.SI.SpecificEnthalpyHdiff (from TwoFluidPorts)specific enthalpy difference: Port B - Port A
Modelica.Units.SI.PressureDifferencePdiff (from TwoFluidPorts)pressure difference: Port B - Port A
IntegerNumActiveTubes (from Pipe)number of parallel identical paths used with flow.
RealSlope (from Pipe)pipe slope as (PortB.Elevation-PortA.Elevation)/Ltube
Modelica.Units.SI.AreaSiActive (from Pipe)active pipe internal surface
Modelica.Units.SI.VolumeViActive (from Pipe)active pipe internal volume
Modelica.Units.SI.AreaSoActive (from Pipe)active pipe external surface
Modelica.Units.SI.VolumeVoActive (from Pipe)active pipe external volume
Modelica.Units.SI.AreaSinsulActive (from Pipe)active pipe external surface
Modelica.Units.SI.DistanceLeTube (from Pipe)equivalent length of the pipe for pressure loss
Modelica.Units.SI.AreaPathSectionActive (from Pipe)section of each tube used for flow calculation
Modelica.Units.SI.DistancePathPerimeterActive (from Pipe)perimeter of each tube used for flow calculation
Modelica.Units.SI.DiameterDh (from Pipe)four time the hydraulic radius
Modelica.Units.SI.MassMassProductTotal (from Pipe)Mass of product inside all the tubes
Modelica.Units.SI.PressurePLossFriction (from Pipe)friction head loss
Modelica.Units.SI.VelocityVa (from PipeFlowBase)
Modelica.Units.SI.VelocityVb (from PipeFlowBase)
Medium.DensityRhoA (from PipeFlowBase)density at Port A
Medium.DensityRhoB (from PipeFlowBase)density at PortB
Medium.ThermodynamicStateStateA (from PipeFlowBase)state at PortA
Medium.ThermodynamicStateStateB (from PipeFlowBase)state at PortB
Modelica.Units.SI.VolumeFlowRateQa (from PipeFlowBase)volume flow rate at PortA
Modelica.Units.SI.VolumeFlowRateQb (from PipeFlowBase)volume flow rate at PortB
Medium.TemperatureTa (from PipeFlowBase)
Medium.TemperatureTb (from PipeFlowBase)
Modelica.Units.SI.PowerW (from PipeFlowBase)heat transfer between fluid and wall. Positive if fluid inputs heat
Medium.DensityRhoLdensity of liquid phase
Medium.DynamicViscosityMuLdynamic viscosity of liquid phase
Modelica.Units.SI.VelocityVlvelocity in each active tube if all was liquid
Modelica.Units.SI.ReynoldsNumberReLReynolds number if all was liquid
RealFlDarcy's friction factor if all liquid
Medium.AbsolutePressurePLossFrictionLfriction head loss if all was liquid
Medium.DensityRhoGdensity of gas phase
Medium.DynamicViscosityMuGdynamic viscosity of gas phase
Modelica.Units.SI.VelocityVgvelocity in each active tube if all was gas
Modelica.Units.SI.ReynoldsNumberReGReynolds number if all was gas
RealFgDarcy's friction factor if all gas
Medium.AbsolutePressurePLossFrictionGfriction head loss if all was gas
FractionXaverage gas fraction
Medium.ThermodynamicStateStateL
Medium.ThermodynamicStateStateG