Modelica.Fluid.Pipes.BaseClasses.HeatTransfer

Heat transfer for flow models

Information

Heat transfer correlations for pipe models

Extends from Modelica.Icons.Package (Icon for standard packages).

Package Content

Name	Description
PartialFlowHeatTransfer	base class for any pipe heat transfer correlation
IdealFlowHeatTransfer	IdealHeatTransfer: Ideal heat transfer without thermal resistance
ConstantFlowHeatTransfer	ConstantHeatTransfer: Constant heat transfer coefficient
PartialPipeFlowHeatTransfer	Base class for pipe heat transfer correlation in terms of Nusselt number heat transfer in a circular pipe for laminar and turbulent one-phase flow
LocalPipeFlowHeatTransfer	LocalPipeFlowHeatTransfer: Laminar and turbulent forced convection in pipes, local coefficients

Modelica.Fluid.Pipes.BaseClasses.HeatTransfer.PartialFlowHeatTransfer

base class for any pipe heat transfer correlation

Information

Base class for heat transfer models of flow devices.

The geometry is specified in the interface with the surfaceAreas[n], the roughnesses[n] and the lengths[n] along the flow path. Moreover the fluid flow is characterized for different types of devices by the characteristic dimensions[n+1] and the average velocities vs[n+1] of fluid flow. See Pipes.BaseClasses.CharacteristicNumbers.ReynoldsNumber for example definitions.

Extends from Modelica.Fluid.Interfaces.PartialHeatTransfer (Common interface for heat transfer models).

Parameters

Name Description

Ambient

k Heat transfer coefficient to ambient [W/(m2.K)]

T_ambient Ambient temperature [K]

Internal Interface

replaceable package Medium Medium in the component

n Number of heat transfer segments

use_k = true to use k value for thermal isolation

Geometry

nParallel number of identical parallel flow devices

Name	Description
Ambient
k	Heat transfer coefficient to ambient [W/(m2.K)]
T_ambient	Ambient temperature [K]
Internal Interface
replaceable package Medium	Medium in the component
n	Number of heat transfer segments
use_k	= true to use k value for thermal isolation
Geometry
nParallel	number of identical parallel flow devices

Connectors

Name Description

heatPorts[n] Heat port to component boundary

Name	Description
heatPorts[n]	Heat port to component boundary

Modelica.Fluid.Pipes.BaseClasses.HeatTransfer.IdealFlowHeatTransfer

IdealHeatTransfer: Ideal heat transfer without thermal resistance

Information

Ideal heat transfer without thermal resistance.

Extends from PartialFlowHeatTransfer (base class for any pipe heat transfer correlation).

Parameters

Name	Description
Ambient
k	Heat transfer coefficient to ambient [W/(m2.K)]
T_ambient	Ambient temperature [K]
Internal Interface
replaceable package Medium	Medium in the component
n	Number of heat transfer segments
use_k	= true to use k value for thermal isolation
Geometry
nParallel	number of identical parallel flow devices

Connectors

Name Description

heatPorts[n] Heat port to component boundary

Name	Description
heatPorts[n]	Heat port to component boundary

Modelica.Fluid.Pipes.BaseClasses.HeatTransfer.ConstantFlowHeatTransfer

ConstantHeatTransfer: Constant heat transfer coefficient

Information

Simple heat transfer correlation with constant heat transfer coefficient, used as default component in distributed pipe models.

Extends from PartialFlowHeatTransfer (base class for any pipe heat transfer correlation).

Parameters

Name Description

alpha0 heat transfer coefficient [W/(m2.K)]

Ambient

k Heat transfer coefficient to ambient [W/(m2.K)]

T_ambient Ambient temperature [K]

Internal Interface

replaceable package Medium Medium in the component

n Number of heat transfer segments

use_k = true to use k value for thermal isolation

Geometry

nParallel number of identical parallel flow devices

Name	Description
alpha0	heat transfer coefficient [W/(m2.K)]
Ambient
k	Heat transfer coefficient to ambient [W/(m2.K)]
T_ambient	Ambient temperature [K]
Internal Interface
replaceable package Medium	Medium in the component
n	Number of heat transfer segments
use_k	= true to use k value for thermal isolation
Geometry
nParallel	number of identical parallel flow devices

Connectors

Name Description

heatPorts[n] Heat port to component boundary

Name	Description
heatPorts[n]	Heat port to component boundary

Modelica.Fluid.Pipes.BaseClasses.HeatTransfer.PartialPipeFlowHeatTransfer

Base class for pipe heat transfer correlation in terms of Nusselt number heat transfer in a circular pipe for laminar and turbulent one-phase flow

Information

Base class for heat transfer models that are expressed in terms of the Nusselt number and which can be used in distributed pipe models.

Extends from PartialFlowHeatTransfer (base class for any pipe heat transfer correlation).

Parameters

Name Description

alpha0 guess value for heat transfer coefficients [W/(m2.K)]

Ambient

k Heat transfer coefficient to ambient [W/(m2.K)]

T_ambient Ambient temperature [K]

Internal Interface

replaceable package Medium Medium in the component

n Number of heat transfer segments

use_k = true to use k value for thermal isolation

Geometry

nParallel number of identical parallel flow devices

Name	Description
alpha0	guess value for heat transfer coefficients [W/(m2.K)]
Ambient
k	Heat transfer coefficient to ambient [W/(m2.K)]
T_ambient	Ambient temperature [K]
Internal Interface
replaceable package Medium	Medium in the component
n	Number of heat transfer segments
use_k	= true to use k value for thermal isolation
Geometry
nParallel	number of identical parallel flow devices

Connectors

Name Description

heatPorts[n] Heat port to component boundary

Name	Description
heatPorts[n]	Heat port to component boundary

Modelica.Fluid.Pipes.BaseClasses.HeatTransfer.LocalPipeFlowHeatTransfer

LocalPipeFlowHeatTransfer: Laminar and turbulent forced convection in pipes, local coefficients

Information

Heat transfer model for laminar and turbulent flow in pipes. Range of validity:

fully developed pipe flow
forced convection
one phase Newtonian fluid
(spatial) constant wall temperature in the laminar region
0 ≤ Re ≤ 1e6, 0.6 ≤ Pr ≤ 100, d/L ≤ 1
The correlation holds for non-circular pipes only in the turbulent region. Use diameter=4*crossArea/perimeter as characteristic length.

The correlation takes into account the spatial position along the pipe flow, which changes discontinuously at flow reversal. However, the heat transfer coefficient itself is continuous around zero flow rate, but not its derivative.

References

Verein Deutscher Ingenieure (1997):: VDI Wärmeatlas. Springer Verlag, Ed. 8, 1997.

Extends from PartialPipeFlowHeatTransfer (Base class for pipe heat transfer correlation in terms of Nusselt number heat transfer in a circular pipe for laminar and turbulent one-phase flow).

Parameters

Name	Description
alpha0	guess value for heat transfer coefficients [W/(m2.K)]
Ambient
k	Heat transfer coefficient to ambient [W/(m2.K)]
T_ambient	Ambient temperature [K]
Internal Interface
replaceable package Medium	Medium in the component
n	Number of heat transfer segments
use_k	= true to use k value for thermal isolation
Geometry
nParallel	number of identical parallel flow devices

Connectors

Name Description

heatPorts[n] Heat port to component boundary

Name	Description
heatPorts[n]	Heat port to component boundary

Automatically generated Mon Sep 23 17:20:46 2013.