Card 9 - TINIT Initial Temperature

KODE

KODE is the code TINIT (or 14)

Option1

N1 is an element number or a group name for the elements whose initial temperatures are specified.

T1 is another element number or 0. T1 must be 0 if N1 is a group name.

T2 is a starting temperature for elements N1 through T1, if T3 is zero. If T2 is zero, then T3 may be of the format:

• Tn, where n is a table number.
• En, where n is an expression number referencing the EXPRESSION card.

T4 and T5 are ignored.

Option 2

N1 is the code FILE.

T1 is a file name from which the temperatures are read. The file must have file TEMPF format.

T2 - T5 are ignored.

Option 3

N1 is the code STEADYSTATE.

If this option is used, and Card 2b specifies a transient run, then a steady state run will be performed before the transient run with the options T1 - T5 to calculate the initial temperatures.

• T1 is the equivalent of the Card 2b GRADNT parameter.
• T2 is the equivalent of the Card 2b DTP parameter.
• T3 is the equivalent of the Card 2b DT parameter.
• T4 is the equivalent of the Card 2b TST parameter.
• T5 is the equivalent of the Card 2b TF parameter.

Code example

TINIT 1 20 15.0
$ ELEMENTS 1 THROUGH 20 HAVE STARTING TEMPF OF 15
$
TINIT 25 0 30.0
$ ELEMENT 25 HAS A STARTING TEMP OF 30 DEGREES
$
TINIT BOX 0 30
$ THE ELEMENTS OF BOX HAVE STARTING TEMP OF 30
$
TINIT FILE TEMPPREV
$ STARTING TEMPS ARE READ FROM FILE TEMPPREV
$
$Spatially varying: TINIT  GroupName  0  0  T25
TABTYPE  25  TEMP  EID
TABDATA  25  Value  Label
Expression: TINIT  Groupname  0  0  E47
EXPRESSION  47  [Expression]

Notes

By default, starting temperatures are read from file TEMPF. If file TEMPF is not present, zero starting temperatures are assumed.

If TINIT Cards are present, they overwrite TEMPF.

For sink elements, you must define temperatures on SINK Cards. Where they conflict with the TINIT Cards, the SINK Card definitions prevail.

Initial temperatures should not be at absolute zero. This is physically unrealistic and may cause convergence problems.