Segregated Solid Energy Model Reference

Note	The Segregated Solid Energy model is not compatible with morphing or with user-defined vertex motion.


Theory	See Heat Transfer.
Provided By	[physics continuum] > Models > Optional Models
Example Node Path	Continua > Physics 1 > Models > Segregated Solid Energy
Requires	Material: Solid or Multi-Component Solid Multi-Component Solid: any
Properties	Secondary Gradients See Segregated Solid Energy Properties.
Activates	Physics Models	Gradient Metrics: Gradients* Equation of State Optional Models: Circumferential Heat Flux Averaging, Moisture Boiling, Thermal Comfort, Thin Film (deprecated)
	Materials	Thermal Conductivity See Materials and Methods.
	Reference Values	Minimum Allowable Temperature Maximum Allowable Temperature See Reference Values.
	Initial Conditions	Static Temperature See Initial Conditions.
	Boundary Inputs	See Boundary Settings.
	Region Inputs	See Region Settings.
	Interface Inputs	See Interface Settings.
	Solvers	Segregated Energy
	Monitors	Energy
	Report Options	Heat Exchanger (Dual Stream) Heat Exchanger (Single Stream) Heat Transfer Temperature Correction See Reports.
	Field Functions	Boundary Conduction Heat Flux Boundary Conduction Heat Transfer Boundary Heat Flux Boundary Heat Flux on External Side Boundary Heat Transfer Density Effective Conductivity External Ambient Temperature External Heat Transfer Coefficient Heat Transfer Coefficient Internal Wall Heat Flux Coefficient, A Internal Wall Heat Flux Coefficient, B Internal Wall Heat Flux Coefficient, C Internal Wall Heat Flux Coefficient, D Local Heat Transfer Coefficient Local Heat Transfer Reference Temperature Net Wall Heat Flux Coefficient, A Net Wall Heat Flux Coefficient, B Net Wall Heat Flux Coefficient, C Net Wall Heat Flux Coefficient, D Porous Solid Conductivity Specific Heat Temperature Temperature Coefficient Temperature on External Side Thermal Conductivity Thermal Conductivity Tensor <nn> Thermal Resistance Time Averaged Boundary Heat Flux Total Energy Total Enthalpy Velocity See Heat Transfer Field Functions Reference.

Segregated Solid Energy Properties

Secondary Gradients

There are two sources of secondary gradients in Simcenter STAR-CCM+ flow solvers:

boundary secondary gradients for diffusion
interior secondary gradients for diffusion at cell faces

Use this property to control which gradients are included in the solver. On gives both gradients while Off excludes them. Interior Only and Boundaries Only select the corresponding gradients.

Materials and Methods

Thermal Conductivity

Specifies the thermal conductivity of the solid material (see

k

in Eqn. (1661)).


Method	Corresponding Method Node
Constant, Field Function, Polynomial in T, Table(T) Suitable for isotropic materials.	Constant, Field Function, Polynomial in T, Table(T) Specifies $k$ as a scalar using either a constant value, a field function, a polynomial function of temperature, or a table of temperature values.
Anisotropic, Orthotropic, Transverse Isotropic Suitable for non-isotropic materials.	Anisotropic, Orthotropic, Transverse Isotropic Specifies $k$ as a second-order tensor. For information on how to define a second-order tensor, see Tensor Quantities. You specify the thermal conductivity orientation as a Region Setting.

Reference Values

Minimum Allowable Temperature

The smallest temperature value that is permitted anywhere in the continuum.

The Energy models (Coupled Energy, Coupled Solid Energy, Segregated Solid Energy, Segregated Fluid Enthalpy, Segregated Fluid Isothermal, Segregated Fluid Temperature) limit temperature corrections such that the corrected value does not go below this minimum. If this occurs, a message is printed to the Output window.

Maximum Allowable Temperature

The largest temperature value that is permitted anywhere in the continuum.

The Energy models (Coupled Energy, Coupled Solid Energy, Segregated Solid Energy, Segregated Fluid Enthalpy, Segregated Fluid Isothermal, Segregated Fluid Temperature) limit temperature corrections such that the corrected value does not exceed this maximum. If this occurs, a message is printed to the Output window.

Initial Conditions

Static Temperature: Sets the initial static temperature in the continuum.

Boundary Settings

Note	Boundary types that do not require setting any conditions or values are not listed.

Wall

Thermal Specification

Allows you to determine how the energy flow across the boundary is specified.


Method	Corresponding Physics Value Nodes
Heat Flux	Heat Flux Specifies the amount of energy flowing across the boundary in W/m². A positive specified heat flux value $q$ means that heat is flowing into the domain. This is opposite to the convention that the boundary heat flux $q_{w} = q \cdot n$ is negative for an inflow of heat (due to outward pointing surface normals at boundaries). The sign of $q$ is switched at this point.
Heat Source	Heat Source Specifies a total heat source in W.
Temperature	Static Temperature Specifies the boundary temperature in K.
Adiabatic Specifies that there is no energy transfer across the boundary.	None.
Convection Specifies convection flux across the boundary in W/m².	Ambient Temperature Specifies the ambient temperature in K. Heat Transfer Coefficient Specifies the heat transfer coefficient in W/m²K.

User Wall Heat Flux Coefficient Specification

Controls whether to specify the heat flux relationship at the boundary.


Method	Corresponding Physics Value Nodes
None Leaves off this feature.	None.
Specified Activates this feature.	User Wall Heat Flux Coefficient, A The user contribution to the constant coefficient of wall heat flux $A$ . User Wall Heat Flux Coefficient, B The user contribution to the cell temperature coefficient of wall heat flux $B$ . User Wall Heat Flux Coefficient, C The user contribution to the wall temperature coefficient of wall heat flux $C$ . User Wall Heat Flux Coefficient, D The user contribution to the wall temperature coefficient of wall heat flux $D$ . The user specified coefficients are added to the internally calculated net coefficients as given by Eqn. (203).
Specified Net Activates this feature for net flux.	Sets the net boundary heat flux coefficients equal to the user specified heat flux coefficients as given by Eqn. (204). This method is available in Multiphase Segregated Flow simulations only.

Contact Interface Boundary

User Wall Heat Flux Coefficient Specification: As for Wall.

Mapped Contact Interface Boundary

Ambient Temperature

Automatically sets the ambient temperature for use with the convection thermal boundary condition.

The value is not mapped directly but uses the Heat Transfer Coefficient and one of the following reference temperatures computed from mapped values of Boundary Heat Flux and Heat Transfer Coefficient:

For no time averaging, uses the Mapped Reference Temperature.
For time averaging, uses the Mapped Average Reference Temperature

This value node becomes available when the Energy Coupling Option at the interface is set to Explicit.

Heat Transfer Coefficient

Automatically sets the heat transfer coefficient for use with the convection thermal boundary condition:

For no time averaging, uses the Mapped Local Heat Transfer Coefficient.
For time averaging, uses the Mapped Averaged Local Heat Transfer Coefficient.

This value node becomes available when the Energy Coupling Option at the interface is set to Explicit.

Time Averaging Option

Sets whether time averaging occurs before mapping across interface boundaries.

This condition node becomes available when the Energy Coupling Option at the interface is set to Explicit and the continuum of the connected region uses an unsteady time model.


Option	Corresponding Value Nodes
Instantaneous	None.
Sliding Window Average Time average of mapped fields over the specified number of previous samples.	Sliding Time Averaging Parameters Exposes the following parameters: Sliding Sample Window Size The number of samples to be averaged. Sampling Delta Time The minimum time between samples used for calculating the average.
Running Average Time average of mapped fields for samples after the specified sampling delay time.	Running Time Averaging Parameters Sampling delay The minimum time before sample collection starts, for averaging, to avoid initial transients.

Region Settings

Thermal Conductivity Orientation

For anisotropic, orthotropic, or transverse isotropic thermal conductivity, specifies the local orientation for the definition of the thermal conductivity tensor, see Orientation Manager and Local Orientations.

Convective Velocity Option

Allows you to activate a convective velocity for simulating energy convection within the solid region. See Convective Velocity Option.


Convective Velocity Option	Corresponding Physics Value Nodes
None Does not apply a convective velocity.	None.
Specified Allows you to specify a convective velocity.	Convective Velocity Rotation is specified by providing an axis of rotation and a rotation rate. The axis of rotations is defined by its origin and its direction. Translation is specified by providing a translation velocity. Direction The direction of the axis of rotation, specified as a vector in the chosen coordinate system. Origin The origin of the axis of rotation, specified as a position vector in the chosen coordinate system. Coordinate System The coordinate system (laboratory by default) for defining the origin and axis. The drop-down list of this property includes any local coordinate systems that exist in the simulation. Rotation Rate The rotation rate around the axis that is specified by Direction and Origin. This is additive with Translation Velocity. Translation Velocity The translation velocity of the region, specified as velocity vector in the chosen coordinate system. This is additive with Rotation Rate.

Energy Source Option

Specifies whether you want to enter an energy source term, and of which type. The energy source corresponds to

S_{u} d V

in Eqn. (1660).


Energy Source Option	Corresponding Physics Value Nodes
None	None.
Volumetric Heat Source	Volumetric Heat Source Specifies a user-defined volumetric heat source in W/m³. Energy Source Temperature Derivative Represents the linearization of the energy source with respect to temperature. Its value is set to zero by default. Providing a value for the derivative helps stabilize the solution when the function for the source term is a function of temperature. If the source is constant, or not a function of temperature, leave this value at zero.
Total Heat Source	Heat Source Specifies a user-defined total heat source in W. If the profile for the heat source uses field functions or user code, the relation between the heat sources for individual cells, as specified by the field function, and the heat source for the entire region is: $h_{c} = h_{t o t} V_{c} / V_{t o t}$ where: $h_{c}$ is heat source for the cell. $h_{t o t}$ is total heat source in the volume or on the surface. $V_{c}$ is the cell volume. $V_{t o t}$ is the total volume. For two-dimensional simulations, the volumes are replaced by surface areas. Energy Source Temperature Derivative As for Volumetric Heat Source.
Specific Heat Source	Specific Heat Source Specifies a user-defined total heat source in W/kg. Energy Source Temperature Derivative As for Volumetric Heat Source.

Interface Settings

Note	Interface types that do not require setting any conditions or values are not listed.

Contact Interface

Thermal Specification

Allows you to specify the thermal conditions at the interface.


Method	Corresponding Physics Value Nodes
Conjugate Heat Transfer The temperature at the interface is determined from the heat transferred through the interface.	Contact Resistance The value of resistance to conduction through the interface. If a field function defines the value and the Ignore Boundary Values property of the field function is activated, the function is computed using data from the cell next to the boundary identified by the Boundary-0 property of the interface.
Specified Temperature The temperature at the interface is the same for both parent boundaries as specified.	Static Temperature The value of the static temperature at the interface.

Energy Source Option

Provides energy source options for the interface.


Method	Corresponding Physics Value Nodes
None	None.
Heat Flux	Heat Flux Specifies the amount of energy flowing across the interface in W/m².
Heat Source	Heat Source Specifies a total heat source in W.

Mapped Contact Interface

The Mapped Contact Interface type is not available if either the Electrodynamic Potential model or the Shell Electrodynamic Potential model is active in both interfacing regions. It is available only if one of the interfacing regions is using either of these two models.

Energy Coupling Option

Specifies implicit or explicit coupling of the energy equation across the interface.


Method	Corresponding Physics Value Nodes
Implicit Set automatically when the interface connects two solid regions. When the interface connects a solid region with a fluid region, use this method when the time scales on both sides are similar.	Contact Resistance The value of resistance to conduction through the interface. If a field function defines the value and the Ignore Boundary Values property of the field function is activated, the function is computed using data from the cell next to the boundary identified by the Boundary-0 property of the interface.
Explicit (only available when the interface connects a solid region with a fluid region) Use this method when the time scales on both sides are very different. This method results in the mapping of thermal fields across the two interface boundaries. It applies a convection thermal boundary condition on the solid interface boundary and a temperature thermal boundary condition on the fluid interface boundary.	None.

Energy Source Option

As for Contact Interface.

This condition node is not available when the Energy Coupling Option at the interface is set to Explicit.

Reports

Heat Exchanger (Dual Stream): Uses calculations with an interface between two regions. This technique involves the heat exchange between a cold fluid stream and a hot fluid stream. These streams are modeled as two different physics continua (each having different material properties). See Heat Exchanger.
Heat Exchanger (Single Stream): Uses calculations with one region. By this method, one stream is assumed to have a uniform temperature and the other stream is modeled by specifying the heat exchanger enthalpy source. See Heat Exchanger.
Heat Transfer: Reports the total heat transfer at a boundary in W. See Heat Transfer.
Temperature Correction: Reports the scaled correction to the temperature calculation at the end of each iteration. See Temperature Correction