7.13.2.5. Temperature Boundary Condition

Scope: Aria Region, Equation System, Explicit Equation System, Root Finder Equation System
Summary: Specified temperature boundary condition.
Description: For this boundary condition, the conservation equations are discarded, and the temperature is completely determined by this boundary condition. The temperature specification must be of exactly one type: e.g., constant, time-dependent, or defined in a user subroutine. If a user subroutine is used, real and integer data may be declared that will be local in scope to this instance of the boundary condition. This data may be accessed using a user query function.

begin Temperature Boundary Condition BC name

   Add Surface SurfaceList...

   Field {=} VariableName

   Integer Data Values...

   Node Subroutine {=} Name

   Real Data Values...

   Temperature {=} Value

   Temperature Fortran Subroutine {=} Name

   Temperature Node Variable {=} Name

   Temperature Scale Factor {=} Magnitude

   Temperature Time Function {=} FunctionName

   Use Data Block Name

   Use Death Name

   Use Toggle Block ToggleName [ {on} ElementBlockList...  ]

   Value {=} VariableValue

end Temperature Boundary Condition BC name

7.13.2.5.1. Line Commands

Add Surface

Syntax: Add Surface SurfaceList…
Summary: Adds surfaces, by name, to a boundary condition’s extent.
Description: This line command is used to add surfaces to the extent of a boundary condition. In Exodus II, surfaces are specified as side sets, that have a global integer identifier. For example, side set 12 would be added by this line command using the surface name surface_12. Note that in SIERRA, each element of an array of strings must be separated by whitespace.

Parameter	Value	Default
SurfaceList	string…	–

Field

Syntax: Field {=} VariableName
Summary: This command can be used with Dirichlet conditions for any solution unknown used in Aria. The FIELD command argument defines the name of the variable to be specified with this boundary condition.

Parameter	Value	Default
{=}	{= \| are \| is}	–
VariableName	string	–

Integer Data

Syntax: Integer Data Values…
Summary: List of integer data values to be used by the FORTRAN user subroutine. Copies of these values are provided to the subroutine hence changes to these values within the subroutine are not saved.

Parameter	Value	Default
Values	integer…	–

Node Subroutine

Syntax: Node Subroutine {=} Name
Summary: Specifies that the named user-defined subroutine be used. At most one subroutine name may be specified for a given quantity. This subroutine must conform to the “node signature” argument list type.

Parameter	Value	Default
{=}	{= \| are \| is}	–
Name	string	–

Real Data

Syntax: Real Data Values…
Summary: List of real data values to be used by the FORTRAN user subroutine. Copies of these values are provided to the subroutine hence changes to these values within the subroutine are not saved.

Parameter	Value	Default
Values	real…	–

Temperature

Syntax: Temperature {=} Value
Summary: Specify the constant value of the temperature. Using this command is equivalent to using both the FIELD = temperature and VALUE = real_value command lines.

Parameter	Value	Default
{=}	{= \| are \| is}	–
Value	real	–

Temperature Fortran Subroutine

Syntax: Temperature Fortran Subroutine {=} Name
Summary: Specify the name of a FORTRAN user subroutine that will be used to calculate the nodal temperature boundary condition.

Parameter	Value	Default
{=}	{= \| are \| is}	–
Name	string	–

Temperature Node Variable

Syntax: Temperature Node Variable {=} Name
Summary: Specify the name of the node variable to use for the temperature associated with this boundary condition.
Description: The indicated node variable must be a legal Aria variable. This variable is defined from the input file in the USER VARIABLE command block or with the USER FIELD command. Two distinct use cases may arise, 1) the variable is calculated in another SIERRA region, e.g., Fuego, and transferred to Aria 2) the variable exists in the input grid file and is populated using the READ VARIABLE command from within the USER FIELD command block.

Parameter	Value	Default
{=}	{= \| are \| is}	–
Name	string	–

Temperature Scale Factor

Syntax: Temperature Scale Factor {=} Magnitude
Summary: Specifies the magnitude by which the distribution factors will be multiplied in order to determine the boundary condition. If this line command is used, node distribution factors must be defined in the input mesh for all nodesets which are associated with this boundary condition.
Description: If this line command is used, node distribution factors must be defined in the input mesh for all nodesets which are associated with this boundary condition. There is currently an inconsistency with respect to temperature boundary conditions and distribution factors: It is not legal to specify sideset distribution factors with the temperature boundary condition: nodesets must be used. Distribution factors also do not work with h-adaptivity, as their values are not currently interpolated to the new nodes. In any case, for temperature boundary conditions, in order for this interpolation to occur, then a sideset would have to be used, which is not supported at this time.

Parameter	Value	Default
{=}	{= \| are \| is}	–
Magnitude	real	–

Temperature Time Function

Syntax: Temperature Time Function {=} FunctionName
Summary: Name of the time-dependent function that specifies the temperature.

Parameter	Value	Default
{=}	{= \| are \| is}	–
FunctionName	string	–

Use Data Block

Syntax: Use Data Block Name
Summary: Reference to predefined data to be used by the user subroutine. These values may be changed by the user subroutine.

Parameter	Value	Default
Name	string	–

Use Death

Syntax

Use Death Name

Summary

Associates this boundary condition with element faces that are created as a result of element death due to the specified element death command block. Note that this line command makes the owning boundary condition have a dynamic extent that changes as elements die.

Description

This line command specifies that the faces that are created as a result of the element death criterion in the named element death command block are added to the extent of this boundary condition. A boundary condition may specify an extent via the “add surface” line command, or the “use death” line command. In this way it is possible to have a boundary condition that is initially empty and then grows dynamically with the surface created as a result of the element death. At least one of these methods must be used.

A boundary condition may be associated with more than one death command block by including this line command more than once. However, to avoid issues of precedence, there is a rule that a given element may not die for more than one reason.

Parameter	Value	Default
Name	string	–

Use Toggle Block

Syntax: Use Toggle Block ToggleName [ {on} ElementBlockList… ]
Summary: Specification for toggling entities in the computational model based on Toggle Block parameters. When used at the region level, the list of element blocks to be toggled must be provided. Otherwise a listing of entities is not needed as the Toggle Block will be associated with the command line or the enclosing command block.

Parameter	Value	Default
ToggleName	string	–

Value

Syntax: Value {=} VariableValue
Summary: This command is used in conjunction with the FIELD command. A constant value of the variable given in the FIELD command is specified with this boundary condition.

Parameter	Value	Default
{=}	{= \| are \| is}	–
VariableValue	string	–