modelShellAndTubesHEXfc
Extends from FreeFluids.HeatExchangers.BaseClasses.ShellAndTubesHEX.
Information
This partial model performs the calculation of the heat transfer coefficient and the pressure drop of a TEMA E shell, according to the Bell-Delaware methodology.The LMTD correction factor is also calculated.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Flow data | |||
| Modelica.Units.SI.Distance | iElevDiff (from HEXtubesDefinition) | 0 | inner pipe differential elevation: out elev. - in elev. |
| Modelica.Units.SI.Distance | oElevDiff (from HEXtubesDefinition) | 0 | outer flow differential elevation: out elev. - in elev. |
| Real | iNumVelocityHeads (from HEXtubesDefinition) | 2*iNumSerial | inner flow number of velocity heads to consider in pressure loss |
| Integer | iNumUturns (from HEXtubesDefinition) | iNumSerial - 1 | number of U turns in each exchanger |
| Inner pipe data | |||
| Boolean | iIsCircular (from HEXtubesDefinition) | true | if false, the inner pipe is not circular |
| Modelica.Units.SI.Distance | iDi (from HEXtubesDefinition) | 0.0 | inner pipe internal diameter, if circular |
| Modelica.Units.SI.Area | iSection (from HEXtubesDefinition) | 0 | inner pipe flow section, if not circular |
| Modelica.Units.SI.Distance | iPerimeter (from HEXtubesDefinition) | 0 | inner pipe perimeter, if not circular |
| Modelica.Units.SI.Distance | iThickness (from HEXtubesDefinition) | 1e-3 | inner pipe thickness |
| Modelica.Units.SI.Distance | iRoughness (from HEXtubesDefinition) | 1.5e-005 | inner pipe roughness. SS:1.5e-5, Steel new:4.6e-5, Steel old:2.0e-4, Concrete:1.5e-3 |
| Modelica.Units.SI.Density | iRhoWall (from HEXtubesDefinition) | 8000 | inner pipe wall density |
| Modelica.Units.SI.ThermalConductivity | iKwall (from HEXtubesDefinition) | 16 | inner pipe wall thermal conductivity. Al=210, Cu=390, Steel=50, SS=17 |
| Modelica.Units.SI.Distance | iLTube (from HEXtubesDefinition) | 0 | stright length of each individual inner pipe |
| Integer | iNumPipes (from HEXtubesDefinition) | 1 | number of inner pipes that form a common pass |
| Integer | iNumParallel (from HEXtubesDefinition) | 1 | number of parallel inner passes. Normally it is the number of exchangers |
| Integer | iNumSerial (from HEXtubesDefinition) | 2 | number of serial inner passes (Each hairpin has two serial passes) |
| Real | pitchRatio (from ShellAndTubesHEX) | 1.33 | ratio between tube pitch and tube diameter. Normally 1.25-1.5 |
| Boolean | triangularPitch (from ShellAndTubesHEX) | true | if false, square layout |
| Boolean | rotatedPitch (from ShellAndTubesHEX) | false | if true, rotated 45º square layout |
| Heat transfer | |||
| Modelica.Units.SI.ThermalInsulance | iFoulingF (from HEXtubesDefinition) | 0.0002 | inner pipe side fouling factor.Typical: 0.00018 for thermal oil, or treated cooling water |
| Modelica.Units.SI.ThermalInsulance | oFoulingF (from HEXtubesDefinition) | 0.0002 | outer flow fouling factor.Typical: 0.00018 for thermal oil, or treated cooling water |
| Boolean | useHTcorr (from HEXtubesDefinition) | true | if true, the heat transfer correction factor is used |
| Boolean | counterCurrent (from HEXtubesDefinition) | true | true if flow is counter-current, otherwise it will be considered co-current |
| Fins data | |||
| Boolean | useFins (from HEXtubesDefinition) | false | if true, fins are taken into account in calculations |
| Modelica.Units.SI.Density | finRho (from HEXtubesDefinition) | 0 | fin density. Al=2700, Cu=8930, Steel=7830, SS=8000 |
| Modelica.Units.SI.ThermalConductivity | finK (from HEXtubesDefinition) | 0 | fin thermal conductivity. Al=210, Cu=390, Steel=50, SS=17 |
| Modelica.Units.SI.Distance | finThickness (from HEXtubesDefinition) | 0.0 | fin thickness |
| Shell data | |||
| Integer | numShells (from ShellAndTubesHEX) | 1 | total number of serial shells |
| Types.TemaShell | shellType (from ShellAndTubesHEX) | Types.TemaShell.E | shell type. Only TEMA E is supported |
| SI.Diameter | dShI (from ShellAndTubesHEX) | 0 | internal shell diameter |
| SI.ShearStress | shellDTS (from ShellAndTubesHEX) | 60.0e6 | shell design tensile stress. AISI316L=60e6. AISI316=68.9e6 |
| SI.Diameter | shellNozzlesDi (from ShellAndTubesHEX) | diameter of shell nozzles | |
| SI.Distance | cTuBa (from ShellAndTubesHEX) | 0.8e-3 | tube-baffle hole diameter clearance. Typical: 0.8 mm |
| SI.Distance | cBaSh (from ShellAndTubesHEX) | 1.6e-3 + 0.004*dShI | baffle-shell diameter clearance. Typical 5 mm |
| SI.Distance | cBuSh (from ShellAndTubesHEX) | 35e-3 | tube bundle-shell diameter clearance. Typical: 35 mm |
| Integer | numBa (from ShellAndTubesHEX) | 23 | |
| Boolean | equalBaffleDistance (from ShellAndTubesHEX) | true | if true, all baffles are at equal distance. If false, inlet and outlet are different |
| SI.Distance | inletBaffleDistance (from ShellAndTubesHEX) | 0 | if equalBaffleDistance=false |
| SI.Distance | outletBaffleDistance (from ShellAndTubesHEX) | 0 | if equalBaffleDistance=false |
| Fraction | BaCutRatio (from ShellAndTubesHEX) | 0.25 | between 0.15 and 0.45 of shell diameter. Normally 0.2-0.35 |
| Integer | numSS (from ShellAndTubesHEX) | 0 | number of sealing strips pairs |
Connectors
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Integer | ItotalNumPipes (from HEXtubesDefinition) | total number of individual inner pipes | |
| Modelica.Units.SI.Distance | IiPerimeter (from HEXtubesDefinition) | inner pipe internal wetted perimeter | |
| Modelica.Units.SI.Area | IiSection (from HEXtubesDefinition) | inner pipe internal flow section | |
| Modelica.Units.SI.Distance | IDh (from HEXtubesDefinition) | internal pipe hydraulic diameter | |
| Modelica.Units.SI.Area | IiArea (from HEXtubesDefinition) | total inner pipes internal heat transfer area | |
| Modelica.Units.SI.Distance | IoPerimeter (from HEXtubesDefinition) | inner pipe external perimeter | |
| Modelica.Units.SI.Area | IoSection (from HEXtubesDefinition) | inner pipe external section | |
| Modelica.Units.SI.Area | IoArea (from HEXtubesDefinition) | total inner pipes external heat transfer area | |
| MediumI.ThermodynamicState | IStateIn (from HEXtubesDefinition) | inner flow inlet state | |
| MediumI.ThermodynamicState | IStateOut (from HEXtubesDefinition) | inner flow outlet state | |
| Modelica.Units.SI.Temperature | ITin (from HEXtubesDefinition) | inner flow inlet temperature | |
| Modelica.Units.SI.Temperature | ITout (from HEXtubesDefinition) | iiner flow outlet temperature | |
| Modelica.Units.SI.Temperature | IT (from HEXtubesDefinition) | inner pipe average temperature | |
| MediumI.ThermodynamicState | IStateWall (from HEXtubesDefinition) | inner pipe wall state for correction factors calculation | |
| Modelica.Units.SI.Temperature | ITwall (from HEXtubesDefinition) | inner pipe wall temperature | |
| Modelica.Units.SI.DynamicViscosity | IMuWall (from HEXtubesDefinition) | inner pipe wall dynamic viscosity | |
| Real | IPlossCorr (from HEXtubesDefinition) | internal pipe pressure loss correction factor | |
| Modelica.Units.SI.AbsolutePressure | IPloss (from HEXtubesDefinition) | internal pipe pressure loss by friction, without taking into account the nozzles | |
| Real | IHTcorr (from HEXtubesDefinition) | internal pipe heat transfer correction factor | |
| Modelica.Units.SI.NusseltNumber | INu (from HEXtubesDefinition) | inner pipe Nusselt number | |
| Modelica.Units.SI.CoefficientOfHeatTransfer | IH (from HEXtubesDefinition) | inner pipe average heat transfer coefficient | |
| MediumO.ThermodynamicState | OStateIn (from HEXtubesDefinition) | outer flow inlet state | |
| MediumO.ThermodynamicState | OStateOut (from HEXtubesDefinition) | outer flow outlet state | |
| Modelica.Units.SI.Temperature | OTin (from HEXtubesDefinition) | outer flow inlet temperature | |
| Modelica.Units.SI.Temperature | OTout (from HEXtubesDefinition) | outer flow outlet temperature | |
| Modelica.Units.SI.Temperature | OT (from HEXtubesDefinition) | outer flow average temperature | |
| Modelica.Units.SI.Length | IEquivLength (from HEXtubesDefinition) | internal pipe equivalent length for pressure drop | |
| Real | OPlossCorr (from HEXtubesDefinition) | outer flow pressure loss correction factor | |
| Modelica.Units.SI.AbsolutePressure | OPloss (from HEXtubesDefinition) | outer flow pressure loss by friction | |
| Modelica.Units.SI.Area | OiArea (from HEXtubesDefinition) | total outer flow internal area for heat transfer | |
| Fraction | OiEfficiency (from HEXtubesDefinition) | outer flow internal area efficiency | |
| Modelica.Units.SI.NusseltNumber | ONu (from HEXtubesDefinition) | outer flow nusselt number for internal heat transfer | |
| Modelica.Units.SI.CoefficientOfHeatTransfer | OHi (from HEXtubesDefinition) | outer flow average heat transfer coefficient to inner pipe | |
| Modelica.Units.SI.ThermalResistance | TRii (from HEXtubesDefinition) | total resitance for the transfer between inner fluid and inner wall | |
| Modelica.Units.SI.ThermalResistance | TRio (from HEXtubesDefinition) | total resitance for the transfer between outer fluid and inner wall | |
| Modelica.Units.SI.ThermalResistance | TRi (from HEXtubesDefinition) | total resitance for the transfer between inner and outer fluids | |
| Modelica.Units.SI.CoefficientOfHeatTransfer | Ui (from HEXtubesDefinition) | global heat transfer coefficient referenced to total inner flow area | |
| Modelica.Units.SI.TemperatureDifference | ILMTD (from HEXtubesDefinition) | LMTD between inner and outer fluids | |
| Fraction | ILMTDcorr (from HEXtubesDefinition) | internal LMTD correction factor | |
| Real | Rntu (from HEXtubesDefinition) | ||
| Real | NTU (from HEXtubesDefinition) | ||
| Modelica.Units.SI.Power | IW (from HEXtubesDefinition) | heat exchanged between inner and outer fluids. Positive if heat enters the inner fluid | |
| Modelica.Units.SI.Area | IiArea1 (from HEXtubesDefinition) | total inner pipes internal heat transfer area used in first stage transfer | |
| Modelica.Units.SI.ThermalResistance | TRi1 (from HEXtubesDefinition) | total resitance for the transfer between inner and outer fluids in the first stage | |
| Integer | TubesInShell (from ShellAndTubesHEX) | ||
| Integer | PassesInShell (from ShellAndTubesHEX) | ||
| Modelica.Units.SI.Diameter | IDo (from ShellAndTubesHEX) | inner pipe external diameter | |
| Real | TubeCountFactor (from ShellAndTubesHEX) | ||
| Real | TubeLayoutFactor (from ShellAndTubesHEX) | ||
| SI.Distance | Pitch (from ShellAndTubesHEX) | should be at least 6 mm more than IDo | |
| SI.Distance | PitchP (from ShellAndTubesHEX) | pitch parallel to flow | |
| SI.Distance | PitchN (from ShellAndTubesHEX) | pitch normal to flow | |
| SI.Diameter | DshIProposal (from ShellAndTubesHEX) | internal shell diameter recommended from number of tubes | |
| SI.Diameter | DbuO (from ShellAndTubesHEX) | tube bundle external diameter | |
| SI.Distance | BaCut (from ShellAndTubesHEX) | max distance from baffle to shell | |
| SI.Distance | BaSep (from ShellAndTubesHEX) | inter baffles distance. Minimum 1/5 of shell diameter or 5 cms. max: 29.54*IDo^0.75. Optimum: 0.3-0.6 of dShI | |
| SI.Angle | ThetaBuC (from ShellAndTubesHEX) | angle of baffle cut intersection with outer tubes centers diameter | |
| SI.Angle | ThetaSh (from ShellAndTubesHEX) | angle of baffle cut intersection with shell | |
| Fraction | Fw (from ShellAndTubesHEX) | fraction of total tubes in each window | |
| Fraction | Fc (from ShellAndTubesHEX) | fraction of total tubes in full crossflow | |
| SI.Area | OSm (from ShellAndTubesHEX) | crossflow area at axis of exchanger | |
| SI.Area | OSBaSh (from ShellAndTubesHEX) | baffle to shell leakage area for each baffle | |
| SI.Area | OSTuBa (from ShellAndTubesHEX) | tube to baffle leakage area for each baffle | |
| SI.Area | OSb (from ShellAndTubesHEX) | bundle bypass area | |
| Real | Nc (from ShellAndTubesHEX) | number of rows in full crossflow | |
| Real | Ncw (from ShellAndTubesHEX) | number of effective crossflow rows in each window | |
| SI.Area | OSw (from ShellAndTubesHEX) | free area for shell flow at windows | |
| Real | Jc | bafflecut correction factor | |
| Real | Jl | baffle leakage correction factor | |
| Real | Jb | Bundle bypass correction factor | |
| Real | Cbh | empirical factor for bundle bypass correction, depending on Reynolds number | |
| Real | Js | unequal baffle spacing correction factor | |
| Real | Jm | wall viscosity correction factor | |
| Real | N | exponent for baffle spacing correction | |
| Real | A1 | ||
| Real | A2 | ||
| Real | A3 | ||
| Real | A4 | empirical constants for ideal heat transfer calculation | |
| Real | B1 | ||
| Real | B2 | ||
| Real | B3 | ||
| Real | B4 | empirical constants for pressure loss calculation | |
| MediumO.ThermodynamicState | OStateAvg | shell average state for physical properties calculation | |
| MediumO.ThermodynamicState | OiStateWall | shell internal wall state for correction factors calculation | |
| Modelica.Units.SI.Density | ORho | shell average density | |
| Modelica.Units.SI.DynamicViscosity | OMu | annulus average dynamic viscosity | |
| Modelica.Units.SI.SpecificHeatCapacity | OCp | shell average heat capacity | |
| Modelica.Units.SI.ThermalConductivity | OK | shell average thermal conductivity | |
| Modelica.Units.SI.DynamicViscosity | OiMuWall | shell inner wall dynamic viscosity | |
| Modelica.Units.SI.PrandtlNumber | OPr | shell Prandt number | |
| Modelica.Units.SI.VolumeFlowRate | OQ | total shell volume flow rate at average conditions | |
| Modelica.Units.SI.Velocity | OV | shell flow velocity at average conditions. Normally between 0.9 and 3.0 m/s for liquids | |
| Modelica.Units.SI.ReynoldsNumber | ORe | shell average Reynolds number | |
| Modelica.Units.SI.CoefficientOfHeatTransfer | OHiIdeal | outer flow ideal heat transfer coefficient to inner pipe | |
| Real | OFcf | crossflow friction factor | |
| SI.Pressure | OPlossCfId | ideal crossflow friction head loss in each baffle compartment | |
| SI.Pressure | OPlossCf | crossflow friction loss for all baffle compartments | |
| Real | Cbp | empirical factor for bundle bypass correction, depending on Reynolds number | |
| Real | Rb | bypass correction factor | |
| Real | Rl | leakage correction factor | |
| SI.Pressure | OPlossWin | windows friction loss for all baffle compartments | |
| SI.Pressure | OPlossEn | entrance friction loss | |
| SI.Pressure | OPlossNoz | nozzles friction loss | |
| Modelica.Units.SI.Velocity | OVnoz | nozzles velocity | |
| Modelica.Units.SI.ReynoldsNumber | OReNoz | nozzles average Reynolds number |