Calculation of mean convective heat transfer coefficient kc of a straight pipe at an uniform wall temperature or uniform heat flux and for a hydrodynamically developed or undeveloped laminar fluid flow. See more information.
Calculation of mean convective heat transfer coefficient kc of a straight pipe for a hydrodynamically developed turbulent fluid flow at uniform wall temperature or uniform heat flux with neglecting or considering of pressure loss influence. See more information.
Calculation of mean convective heat transfer coefficient kc of a straight pipe at an uniform wall temperature or uniform heat flux and for a hydrodynamically developed or undeveloped laminar and turbulent fluid flow with neglect or consideration of pressure loss influence. See more information.
Calculation of local two phase heat transfer coefficient kc_2ph for (horizontal/vertical) boiling or (horizontal) condensation for an overall flow regime. See more information.
Extends from Modelica.Icons.VariantsPackage (Icon for package containing variants).
| Name | Description |
|---|---|
 kc_laminar
| Mean heat transfer coefficient of straight pipe | uniform wall temperature or uniform heat flux | hydrodynamically developed or undeveloped laminar flow regime |
| kc_laminar_KC
| Mean heat transfer coefficient of straight pipe | uniform wall temperature or uniform heat flux | hydrodynamically developed or undeveloped laminar flow regime |
 kc_laminar_IN_con
| Input record for function kc_laminar and kc_laminar_KC |
| kc_laminar_IN_var
| Input record for function kc_laminar and kc_laminar_KC |
 kc_overall
| Mean heat transfer coefficient of straight pipe | uniform wall temperature or uniform heat flux | hydrodynamically developed or undeveloped overall flow regime| pressure loss dependence |
| kc_overall_KC
| Mean heat transfer coefficient of straight pipe | uniform wall temperature or uniform heat flux | hydrodynamically developed or undeveloped overall flow regime| pressure loss dependence |
 kc_overall_IN_con
| Input record for function kc_overall and kc_overall_KC |
| kc_overall_IN_var
| Input record for function kc_overall and kc_overall_KC |
 kc_turbulent
| Mean heat transfer coefficient of straight pipe | hydrodynamically developed turbulent flow regime | pressure loss dependence |
| kc_turbulent_KC
| Mean heat transfer coefficient of straight pipe | hydrodynamically developed turbulent flow regime | pressure loss dependence |
 kc_turbulent_IN_con
| Input record for function kc_turbulent and kc_turbulent_KC |
| kc_turbulent_IN_var
| Input record for function kc_turbulent and kc_turbulent_KC |
 kc_twoPhaseOverall_KC
| Local two phase heat transfer coefficient of straight pipe | horizontal or vertical boiling | horizontal condensation |
 kc_twoPhaseOverall_KC_IN_con
| Input record for function kc_twoPhaseOverall_KC |
| kc_twoPhaseOverall_KC_IN_var
| Input record for function kc_twoPhaseOverall_KC |
Calculation of mean convective heat transfer coefficient kc of a straight pipe at an uniform wall temperature or uniform heat flux and for a hydrodynamically developed or undeveloped laminar fluid flow. Note that additionally a failure status is observed in this function to check if the intended boundary conditions are fulfilled. See more information .
| Type | Name | Default | Description |
|---|---|---|---|
| Constant inputs | |||
| kc_laminar_IN_con | IN_con | Input record for function kc_laminar | |
| Variable inputs | |||
| kc_laminar_IN_var | IN_var | Input record for function kc_laminar | |
| Type | Name | Description |
|---|---|---|
| Output | ||
| CoefficientOfHeatTransfer | kc | Convective heat transfer coefficient [W/(m2.K)] |
| PrandtlNumber | Pr | Prandl number [1] |
| ReynoldsNumber | Re | Reynolds number [1] |
| NusseltNumber | Nu | Nusselt number [1] |
| Real | failureStatus | 0== boundary conditions fulfilled | 1== failure >> check if still meaningfull results |
function kc_laminar
"Mean heat transfer coefficient of straight pipe | uniform wall temperature or uniform heat flux | hydrodynamically developed or undeveloped laminar flow regime"
//input records
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_laminar_IN_con
IN_con "Input record for function kc_laminar";
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_laminar_IN_var
IN_var "Input record for function kc_laminar";
//output variables
output SI.CoefficientOfHeatTransfer kc "Convective heat transfer coefficient";
output SI.PrandtlNumber Pr "Prandl number";
output SI.ReynoldsNumber Re "Reynolds number";
output SI.NusseltNumber Nu "Nusselt number";
output Real failureStatus
"0== boundary conditions fulfilled | 1== failure >> check if still meaningfull results";
protected
Real MIN=Modelica.Constants.eps;
Real laminar=2e3 "Maximum Reynolds number of laminar flow regime";
Real prandtlMax=1000 "Maximum Prandtl number";
Real prandtlMin=0.6 "Minimum Prandtl number";
SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Cross sectional area";
SI.Velocity velocity=abs(IN_var.m_flow)/max(MIN, IN_var.rho*A_cross)
"Mean velocity";
//failure status
Real fstatus[2] "check of expected boundary conditions";
//Documentation
algorithm
Pr := abs(IN_var.eta*IN_var.cp/max(MIN, IN_var.lambda));
Re := max(1e-3, IN_var.rho*velocity*IN_con.d_hyd/max(MIN, IN_var.eta));
kc := Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_laminar_KC(IN_con, IN_var);
Nu := kc*IN_con.d_hyd/max(MIN, IN_var.lambda);
//failure status
fstatus[1] := if Re > laminar then 1 else 0;
fstatus[2] := if Pr > prandtlMax or Pr < prandtlMin then 1 else 0;
failureStatus := 0;
for i in 1:size(fstatus, 1) loop
if fstatus[i] == 1 then
failureStatus := 1;
end if;
end for;
end kc_laminar;
Calculation of mean convective heat transfer coefficient kc of a straight pipe at an uniform wall temperature or uniform heat flux and for a hydrodynamically developed or undeveloped laminar fluid flow. See more information .
| Type | Name | Default | Description |
|---|---|---|---|
| Constant inputs | |||
| kc_laminar_IN_con | IN_con | Input record for function kc_laminar_KC | |
| Variable inputs | |||
| kc_laminar_IN_var | IN_var | Input record for function kc_laminar_KC | |
| Type | Name | Description |
|---|---|---|
| CoefficientOfHeatTransfer | kc | Output for function kc_laminar_KC [W/(m2.K)] |
function kc_laminar_KC
"Mean heat transfer coefficient of straight pipe | uniform wall temperature or uniform heat flux | hydrodynamically developed or undeveloped laminar flow regime"
//input records
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_laminar_IN_con
IN_con "Input record for function kc_laminar_KC";
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_laminar_IN_var
IN_var "Input record for function kc_laminar_KC";
//output variables
output SI.CoefficientOfHeatTransfer kc "Output for function kc_laminar_KC";
protected
type TYP =
Modelica.Fluid.Dissipation.Utilities.Types.HeatTransferBoundary;
Real MIN=Modelica.Constants.eps;
SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Circular cross sectional area";
Real Nu0=if IN_con.target == TYP.UWTuDFF or IN_con.target == TYP.UWTuUFF then
0.7 else if IN_con.target == TYP.UHFuDFF or IN_con.target == TYP.UHFuUFF then
0.6 else 0 "Help variable for mean Nusselt number";
Real Nu1=if IN_con.target == TYP.UWTuDFF or IN_con.target == TYP.UWTuUFF then
3.66 else if IN_con.target == TYP.UHFuDFF or IN_con.target == TYP.UHFuUFF then
4.364 else 0 "Help variable for mean Nusselt number";
SI.Velocity velocity=abs(IN_var.m_flow)/max(MIN, IN_var.rho*A_cross)
"Mean velocity";
SI.ReynoldsNumber Re=max(1e-3, IN_var.rho*velocity*IN_con.d_hyd/max(MIN,
IN_var.eta));
SI.PrandtlNumber Pr=abs(IN_var.eta*IN_var.cp/max(MIN, IN_var.lambda));
SI.NusseltNumber Nu2=if IN_con.target == TYP.UWTuDFF or IN_con.target == TYP.UWTuUFF then
1.615*(Re*Pr*IN_con.d_hyd/IN_con.L)^(1/3) else if IN_con.target ==
TYP.UHFuDFF or IN_con.target == TYP.UHFuUFF then 1.953*(Re*Pr*IN_con.d_hyd
/IN_con.L)^(1/3) else 0 "Help variable for mean Nusselt number";
SI.NusseltNumber Nu3=if IN_con.target == TYP.UWTuUFF then (2/(1 + 22*Pr))^(1/
6)*(Re*Pr*IN_con.d_hyd/IN_con.L)^0.5 else if IN_con.target == TYP.UHFuUFF then
1.953*(Re*Pr*IN_con.d_hyd/IN_con.L)^(1/3) else 0
"Help variable for mean Nusselt number";
SI.NusseltNumber Nu=(Nu1^3 + Nu0^3 + (Nu2 - Nu0)^3 + Nu3^3)^(1/3)
"Mean Nusselt number";
//Documentation
algorithm
kc := Nu*IN_var.lambda/max(MIN, IN_con.d_hyd);
end kc_laminar_KC;
Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_laminar_IN_con
Extends from Utilities.Records.HeatTransfer.StraightPipe (Input for straight pipe).
| Type | Name | Default | Description |
|---|---|---|---|
| Straight pipe | |||
| Diameter | d_hyd | 0.1 | Hydraulic diameter [m] |
| Length | L | 1 | Length [m] |
| Choices | |||
| HeatTransferBoundary | target | Dissipation.Utilities.Types.... | Choice of heat transfer boundary condition |
record kc_laminar_IN_con
"Input record for function kc_laminar and kc_laminar_KC"
extends Utilities.Records.HeatTransfer.StraightPipe;
//choices
Modelica.Fluid.Dissipation.Utilities.Types.HeatTransferBoundary target=Dissipation.Utilities.Types.HeatTransferBoundary.UWTuDFF
"Choice of heat transfer boundary condition";
end kc_laminar_IN_con;
Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_laminar_IN_var
Extends from Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_var (Input record for function kc_overall and kc_overall_KC).
| Type | Name | Default | Description |
|---|---|---|---|
| Fluid properties | |||
| SpecificHeatCapacityAtConstantPressure | cp | Specific heat capacity of fluid at constant pressure [J/(kg.K)] | |
| DynamicViscosity | eta | Dynamic viscosity of fluid [Pa.s] | |
| ThermalConductivity | lambda | Thermal conductivity of fluid [W/(m.K)] | |
| Density | rho | Density of fluid [kg/m3] | |
| Input | |||
| MassFlowRate | m_flow | [kg/s] | |
record kc_laminar_IN_var "Input record for function kc_laminar and kc_laminar_KC" extends Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_var;end kc_laminar_IN_var;
Calculation of mean convective heat transfer coefficient kc of a straight pipe at an uniform wall temperature or uniform heat flux and for a hydrodynamically developed or undeveloped overall fluid flow with neglect or consideration of pressure loss influence. Note that additionally a failure status is observed in this function to check if the intended boundary conditions are fulfilled. See more information .
| Type | Name | Default | Description |
|---|---|---|---|
| Constant inputs | |||
| kc_overall_IN_con | IN_con | Input record for function kc_overall | |
| Variable inputs | |||
| kc_overall_IN_var | IN_var | Input record for function kc_overall | |
| Type | Name | Description |
|---|---|---|
| Output | ||
| CoefficientOfHeatTransfer | kc | Convective heat transfer coefficient [W/(m2.K)] |
| PrandtlNumber | Pr | Prandl number [1] |
| ReynoldsNumber | Re | Reynolds number [1] |
| NusseltNumber | Nu | Nusselt number [1] |
| Real | failureStatus | 0== boundary conditions fulfilled | 1== failure >> check if still meaningfull results |
function kc_overall
"Mean heat transfer coefficient of straight pipe | uniform wall temperature or uniform heat flux | hydrodynamically developed or undeveloped overall flow regime| pressure loss dependence"
//input records
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_con
IN_con "Input record for function kc_overall";
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_var
IN_var "Input record for function kc_overall";
//output variables
output SI.CoefficientOfHeatTransfer kc "Convective heat transfer coefficient";
output SI.PrandtlNumber Pr "Prandl number";
output SI.ReynoldsNumber Re "Reynolds number";
output SI.NusseltNumber Nu "Nusselt number";
output Real failureStatus
"0== boundary conditions fulfilled | 1== failure >> check if still meaningfull results";
protected
type TYP = Modelica.Fluid.Dissipation.Utilities.Types.Roughness;
Real MIN=Modelica.Constants.eps;
SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Cross sectional area";
SI.Velocity velocity=abs(IN_var.m_flow)/max(MIN, IN_var.rho*A_cross)
"Mean velocity";
//failure status
Real fstatus[3] "Check of expected boundary conditions";
//Documentation
algorithm
Pr := abs(IN_var.eta*IN_var.cp/max(MIN, IN_var.lambda));
Re := max(1e-3, IN_var.rho*velocity*IN_con.d_hyd/max(MIN, IN_var.eta));
kc := Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_KC(IN_con, IN_var);
Nu := kc*IN_con.d_hyd/max(MIN, IN_var.lambda);
//failure status
if IN_con.roughness == TYP.Neglected then
if Re < 2e4 or Re > 1e6 then
fstatus[1] := 1;
else
fstatus[1] := 0;
end if;
elseif IN_con.roughness == TYP.Considered then
if Re < 1e4 or Re > 1e6 then
fstatus[1] := 1;
else
fstatus[1] := 0;
end if;
else
assert(true, "No choice of roughness is selected");
end if;
fstatus[2] := if Pr < 0.6 or Pr > 1e3 then 1 else 0;
fstatus[3] := if IN_con.d_hyd/max(MIN, IN_con.L) > 1 then 1 else 0;
failureStatus := 0;
for i in 1:size(fstatus, 1) loop
if fstatus[i] == 1 then
failureStatus := 1;
end if;
end for;
end kc_overall;
Calculation of mean convective heat transfer coefficient kc of a straight pipe at an uniform wall temperature or uniform heat flux and for a hydrodynamically developed or undeveloped overall fluid flow with neglect or consideration of pressure loss influence.See more information .
| Type | Name | Default | Description |
|---|---|---|---|
| Constant inputs | |||
| kc_overall_IN_con | IN_con | Input record for function kc_overall_KC | |
| Variable inputs | |||
| kc_overall_IN_var | IN_var | Input record for function kc_overall_KC | |
| Type | Name | Description |
|---|---|---|
| CoefficientOfHeatTransfer | kc | Output for function kc_overall_KC [W/(m2.K)] |
function kc_overall_KC
"Mean heat transfer coefficient of straight pipe | uniform wall temperature or uniform heat flux | hydrodynamically developed or undeveloped overall flow regime| pressure loss dependence"
import SMOOTH = Modelica.Fluid.Dissipation.Utilities.Functions.General.Stepsmoother;
//input records
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_con
IN_con "Input record for function kc_overall_KC";
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_var
IN_var "Input record for function kc_overall_KC";
//output variables
output SI.CoefficientOfHeatTransfer kc "Output for function kc_overall_KC";
protected
Real MIN=Modelica.Constants.eps;
Real laminar=2200 "Maximum Reynolds number for laminar regime";
Real turbulent=1e4 "Minimum Reynolds number for turbulent regime";
SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Cross sectional area";
SI.Velocity velocity=abs(IN_var.m_flow)/max(MIN, IN_var.rho*A_cross)
"Mean velocity";
SI.ReynoldsNumber Re=max(1e-3, IN_var.rho*velocity*IN_con.d_hyd/max(MIN,
IN_var.eta));
SI.PrandtlNumber Pr=abs(IN_var.eta*IN_var.cp/max(MIN, IN_var.lambda));
//Documentation
algorithm
kc := SMOOTH(
laminar,
turbulent,
Re)*Dissipation.HeatTransfer.StraightPipe.kc_laminar_KC(IN_con,
IN_var) + SMOOTH(
turbulent,
laminar,
Re)*Dissipation.HeatTransfer.StraightPipe.kc_turbulent_KC(
IN_con, IN_var);
end kc_overall_KC;
Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_con
Extends from kc_turbulent_IN_con (Input record for function kc_turbulent and kc_turbulent_KC).
| Type | Name | Default | Description |
|---|---|---|---|
| Choices | |||
| HeatTransferBoundary | target | Dissipation.Utilities.Types.... | Choice of heat transfer boundary condition |
| Roughness | roughness | Dissipation.Utilities.Types.... | Choice of considering surface roughness |
| Straight pipe | |||
| Diameter | d_hyd | 0.1 | Hydraulic diameter [m] |
| Length | L | 1 | Length [m] |
| Length | K | 0 | Roughness (average height of surface asperities) [m] |
record kc_overall_IN_con
"Input record for function kc_overall and kc_overall_KC"
//choices
Modelica.Fluid.Dissipation.Utilities.Types.HeatTransferBoundary target=Dissipation.Utilities.Types.HeatTransferBoundary.UWTuDFF
"Choice of heat transfer boundary condition";
extends kc_turbulent_IN_con;
end kc_overall_IN_con;
Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_var
Extends from Modelica.Fluid.Dissipation.Utilities.Records.General.FluidProperties (Base record for fluid properties).
| Type | Name | Default | Description |
|---|---|---|---|
| Fluid properties | |||
| SpecificHeatCapacityAtConstantPressure | cp | Specific heat capacity of fluid at constant pressure [J/(kg.K)] | |
| DynamicViscosity | eta | Dynamic viscosity of fluid [Pa.s] | |
| ThermalConductivity | lambda | Thermal conductivity of fluid [W/(m.K)] | |
| Density | rho | Density of fluid [kg/m3] | |
| Input | |||
| MassFlowRate | m_flow | [kg/s] | |
record kc_overall_IN_var "Input record for function kc_overall and kc_overall_KC" //fluid property variables extends Modelica.Fluid.Dissipation.Utilities.Records.General.FluidProperties; //input variable (mass flow rate) SI.MassFlowRate m_flow;end kc_overall_IN_var;
Calculation of mean convective heat transfer coefficient kc of a straight pipe for a hydrodynamically developed turbulent fluid flow at uniform wall temperature or uniform heat flux with neglecting or considering of pressure loss influence. Note that additionally a failure status is observed in this function to check if the intended boundary conditions are fulfilled. See more information .
| Type | Name | Default | Description |
|---|---|---|---|
| Constant inputs | |||
| kc_turbulent_IN_con | IN_con | Input record for function kc_turbulent | |
| Variable inputs | |||
| kc_turbulent_IN_var | IN_var | Input record for function kc_turbulent | |
| Type | Name | Description |
|---|---|---|
| Output | ||
| CoefficientOfHeatTransfer | kc | Convective heat transfer coefficient [W/(m2.K)] |
| PrandtlNumber | Pr | Prandl number [1] |
| ReynoldsNumber | Re | Reynolds number [1] |
| NusseltNumber | Nu | Nusselt number [1] |
| Real | failureStatus | 0== boundary conditions fulfilled | 1== failure >> check if still meaningfull results |
function kc_turbulent
"Mean heat transfer coefficient of straight pipe | hydrodynamically developed turbulent flow regime | pressure loss dependence"
//input records
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_turbulent_IN_con
IN_con "Input record for function kc_turbulent";
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_turbulent_IN_var
IN_var "Input record for function kc_turbulent";
//output variables
output SI.CoefficientOfHeatTransfer kc "Convective heat transfer coefficient";
output SI.PrandtlNumber Pr "Prandl number";
output SI.ReynoldsNumber Re "Reynolds number";
output SI.NusseltNumber Nu "Nusselt number";
output Real failureStatus
"0== boundary conditions fulfilled | 1== failure >> check if still meaningfull results";
protected
type TYP = Modelica.Fluid.Dissipation.Utilities.Types.Roughness;
Real MIN=Modelica.Constants.eps;
SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Cross sectional area";
SI.Velocity velocity=abs(IN_var.m_flow)/(IN_var.rho*A_cross) "Mean velocity";
//failure status
Real fstatus[3] "check of expected boundary conditions";
//Documentation
algorithm
Pr := abs(IN_var.eta*IN_var.cp/max(MIN, IN_var.lambda));
Re := max(1e-3, IN_var.rho*velocity*IN_con.d_hyd/max(MIN, IN_var.eta));
kc := Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_turbulent_KC(IN_con, IN_var);
Nu := kc*IN_con.d_hyd/max(MIN, IN_var.lambda);
//failure status
if IN_con.roughness == TYP.Neglected then
if Re < 2e4 or Re > 1e6 then
fstatus[1] := 1;
else
fstatus[1] := 0;
end if;
elseif IN_con.roughness == TYP.Considered then
if Re < 1e4 or Re > 1e6 then
fstatus[1] := 1;
else
fstatus[1] := 0;
end if;
else
assert(true, "No choice of roughness is selected");
end if;
fstatus[2] := if Pr <= 0.6 or Pr >= 1e3 then 1 else 0;
fstatus[3] := if IN_con.d_hyd/max(MIN, IN_con.L) > 1 then 1 else 0;
failureStatus := 0;
for i in 1:size(fstatus, 1) loop
if fstatus[i] == 1 then
failureStatus := 1;
end if;
end for;
end kc_turbulent;
Calculation of mean convective heat transfer coefficient kc of a straight pipe for a hydrodynamically developed turbulent fluid flow at uniform wall temperature or uniform heat flux with neglecting or considering of pressure loss influence. See more information .
| Type | Name | Default | Description |
|---|---|---|---|
| Constant inputs | |||
| kc_turbulent_IN_con | IN_con | Input record for function kc_turbulent_KC | |
| Variable inputs | |||
| kc_turbulent_IN_var | IN_var | Input record for function kc_turbulent_KC | |
| Type | Name | Description |
|---|---|---|
| CoefficientOfHeatTransfer | kc | Output for function kc_turbulent_KC [W/(m2.K)] |
function kc_turbulent_KC
"Mean heat transfer coefficient of straight pipe | hydrodynamically developed turbulent flow regime | pressure loss dependence"
//input records
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_turbulent_IN_con
IN_con "Input record for function kc_turbulent_KC";
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_turbulent_IN_var
IN_var "Input record for function kc_turbulent_KC";
//output variables
output SI.CoefficientOfHeatTransfer kc "Output for function kc_turbulent_KC";
protected
type TYP = Modelica.Fluid.Dissipation.Utilities.Types.Roughness;
Real MIN=Modelica.Constants.eps;
SI.Area A_cross=PI*IN_con.d_hyd^2/4 "Circular cross sectional area";
SI.Velocity velocity=abs(IN_var.m_flow)/(IN_var.rho*A_cross) "Mean velocity";
SI.ReynoldsNumber Re=max(2.6, IN_var.rho*velocity*IN_con.d_hyd/IN_var.eta);
SI.PrandtlNumber Pr=abs(IN_var.eta*IN_var.cp/IN_var.lambda);
Real zeta=abs(1/max(MIN, 1.8*Modelica.Math.log10(abs(Re)) - 1.5)^2)
"Pressure loss coefficient";
//Documentation
algorithm
kc := if IN_con.roughness == TYP.Neglected then abs(IN_var.lambda/IN_con.d_hyd)
*0.023*Re^0.8*Pr^(1/3) else if IN_con.roughness == TYP.Considered then abs(
IN_var.lambda/IN_con.d_hyd)*(abs(zeta)/8)*abs(Re)*abs(Pr)/(1 + 12.7*(abs(
zeta)/8)^0.5*(abs(Pr)^(2/3) - 1))*(1 + (IN_con.d_hyd/IN_con.L)^(2/3)) else
0;
end kc_turbulent_KC;
Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_turbulent_IN_con
Extends from Utilities.Records.HeatTransfer.StraightPipe (Input for straight pipe).
| Type | Name | Default | Description |
|---|---|---|---|
| Straight pipe | |||
| Diameter | d_hyd | 0.1 | Hydraulic diameter [m] |
| Length | L | 1 | Length [m] |
| Length | K | 0 | Roughness (average height of surface asperities) [m] |
| Choices | |||
| Roughness | roughness | Dissipation.Utilities.Types.... | Choice of considering surface roughness |
record kc_turbulent_IN_con
"Input record for function kc_turbulent and kc_turbulent_KC"
extends Utilities.Records.HeatTransfer.StraightPipe;
Modelica.Fluid.Dissipation.Utilities.Types.Roughness roughness=Dissipation.Utilities.Types.Roughness.Considered
"Choice of considering surface roughness";
SI.Length K=0 "Roughness (average height of surface asperities)";
end kc_turbulent_IN_con;
Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_turbulent_IN_var
Extends from Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_var (Input record for function kc_overall and kc_overall_KC).
| Type | Name | Default | Description |
|---|---|---|---|
| Fluid properties | |||
| SpecificHeatCapacityAtConstantPressure | cp | Specific heat capacity of fluid at constant pressure [J/(kg.K)] | |
| DynamicViscosity | eta | Dynamic viscosity of fluid [Pa.s] | |
| ThermalConductivity | lambda | Thermal conductivity of fluid [W/(m.K)] | |
| Density | rho | Density of fluid [kg/m3] | |
| Input | |||
| MassFlowRate | m_flow | [kg/s] | |
record kc_turbulent_IN_var "Input record for function kc_turbulent and kc_turbulent_KC" extends Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_overall_IN_var;end kc_turbulent_IN_var;
Calculation of local two phase heat transfer coefficient kc_2ph for (horizontal/vertical) boiling or (horizontal) condensation for an overall flow regime. See more information .
| Type | Name | Default | Description |
|---|---|---|---|
| Constant inputs | |||
| kc_twoPhaseOverall_KC_IN_con | IN_con | ||
| Variable inputs | |||
| kc_twoPhaseOverall_KC_IN_var | IN_var | ||
| Type | Name | Description |
|---|---|---|
| CoefficientOfHeatTransfer | kc | Local two phase heat transfer coefficient [W/(m2.K)] |
function kc_twoPhaseOverall_KC
"Local two phase heat transfer coefficient of straight pipe | horizontal or vertical boiling | horizontal condensation"
//SOURCE_1: Bejan,A.: HEAT TRANSFER HANDBOOK, Wiley, 2003.
//SOURCE_2: Gungor, K.E. and R.H.S. Winterton: A general correlation for flow boiling in tubes and annuli, Int.J. Heat Mass Transfer, Vol.29, p.351-358, 1986.
//input records
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_twoPhaseOverall_KC_IN_con
IN_con;
input Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_twoPhaseOverall_KC_IN_var
IN_var;
//output variables
output SI.CoefficientOfHeatTransfer kc
"Local two phase heat transfer coefficient";
protected
Real MIN=Modelica.Constants.eps;
//Documentation
algorithm
kc := if IN_con.target == Modelica.Fluid.Dissipation.Utilities.Types.TwoPhaseHeatTransferTarget.BoilHor then
Modelica.Fluid.Dissipation.Utilities.Functions.HeatTransfer.TwoPhase.kc_twoPhase_boilingHorizontal_KC(
IN_con, IN_var) else if IN_con.target == Modelica.Fluid.Dissipation.Utilities.Types.TwoPhaseHeatTransferTarget.BoilVer then
Modelica.Fluid.Dissipation.Utilities.Functions.HeatTransfer.TwoPhase.kc_twoPhase_boilingVertical_KC(
IN_con, IN_var) else if IN_con.target == Modelica.Fluid.Dissipation.Utilities.Types.TwoPhaseHeatTransferTarget.CondHor then
Modelica.Fluid.Dissipation.Utilities.Functions.HeatTransfer.TwoPhase.kc_twoPhase_condensationHorizontal_KC(
IN_con, IN_var) else MIN;
end kc_twoPhaseOverall_KC;
Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_twoPhaseOverall_KC_IN_con
Extends from Modelica.Fluid.Dissipation.Utilities.Records.HeatTransfer.TwoPhaseFlowHT_IN_con (Base record for two phase heat transfer coefficient).
| Type | Name | Default | Description |
|---|---|---|---|
| Choices | |||
| TwoPhaseHeatTransferTarget | target | Modelica.Fluid.Dissipation.U... | Choice of (horizontal/vertical) boiling or (horizontal) condensation in pipe |
| Geometry | |||
| Area | A_cross | Modelica.Constants.pi*0.1^2/4 | Cross sectional area [m2] |
| Length | perimeter | Modelica.Constants.pi*0.1 | Wettet perimeter [m] |
| Fluid properties | |||
| MolarMass | MM | 0.018015268 | Molar mass of fluid [kg/mol] |
| Pressure | p_crit | Critical pressure of fluid [Pa] | |
record kc_twoPhaseOverall_KC_IN_con "Input record for function kc_twoPhaseOverall_KC" extends Modelica.Fluid.Dissipation.Utilities.Records.HeatTransfer.TwoPhaseFlowHT_IN_con;end kc_twoPhaseOverall_KC_IN_con;
Modelica.Fluid.Dissipation.HeatTransfer.StraightPipe.kc_twoPhaseOverall_KC_IN_var
Extends from Modelica.Fluid.Dissipation.Utilities.Records.HeatTransfer.TwoPhaseFlowHT_IN_var (Base record for two phase heat transfer coefficient).
| Type | Name | Default | Description |
|---|---|---|---|
| Choices | |||
| TwoPhaseHeatTransferTarget | target | Modelica.Fluid.Dissipation.U... | Choice of (horizontal/vertical) boiling or (horizontal) condensation in pipe |
| Fluid properties | |||
| SpecificHeatCapacityAtConstantPressure | cp_l | Specific heat capacity of liquid [J/(kg.K)] | |
| ThermalConductivity | lambda_l | Thermal conductivity of liquid [W/(m.K)] | |
| Density | rho_g | Density of gas [kg/m3] | |
| Density | rho_l | Density of liquid [kg/m3] | |
| DynamicViscosity | eta_g | Dynamic viscosity of gas [Pa.s] | |
| DynamicViscosity | eta_l | Dynamic viscosity of liquid [Pa.s] | |
| Pressure | pressure | Mean pressure of fluid [Pa] | |
| SpecificEnthalpy | dh_lg | Evaporation enthalpy of fluid [J/kg] | |
| Input | |||
| MassFlowRate | m_flow | Mass flow rate [kg/s] | |
| HeatFlux | qdot_A | 0 | Heat flux at boiling [W/m2] |
| Real | x_flow | 0 | Mass flow rate quality |
record kc_twoPhaseOverall_KC_IN_var "Input record for function kc_twoPhaseOverall_KC" extends Modelica.Fluid.Dissipation.Utilities.Records.HeatTransfer.TwoPhaseFlowHT_IN_var;end kc_twoPhaseOverall_KC_IN_var;