Element thermal data
The USER1 code modifies element thermal which influence the solution of
the thermal model. This section describes where that data is stored and when to modify
it. The 'when' is important, there is little point in changing element temperatures if
thermal solver itself recalculates then before using them to recalculate
conductances.
Element thermal data is contained in arrays that are either arguments to
USER1 or in common blocks. Modifying the element data simply
requires changing the values in the array. The all arrays use internal element labels as
indices. There is an exception. For more information, see the total pressure entry in
the element thermal data table.
TMG models contain two types of elements, thermal and fluid. The number of thermal
elements is contained in the variable MAXN1, the number of fluid
elements is contained in the variable MAXN2. The total number of
elements is stored in the variable MAXNO, and clearly:
MAXNO = MAXN1 + MAXN2
The internal numbering system is such that elements 1 -
MAXN1 are the thermal elements and elements (MAXN1
+ 1) - MAXN2 are the fluid elements.
MAXN1, MAXN2 and
MAXNO should not be changed by the user code.The element thermal data and the time to modify them are listed in the following table.
| Thermal data | Storage | Modification and notes |
|---|---|---|
| Element capacitance | Array C(j) | Modify when argument KODE = 1
Sink elements and Moving Control Volume elements are assigned
capacitances values |
| Heat load on element | Array Q(k) | Modify when argument KODE = 1This is the current total heat load on the element from all sources. TMG reassigns the value every iteration, therefore any changes must be made at every iteration. |
| Fraction of phase change | Array QD(k) | Modify when argument KODE = 1This is the fraction of the element that is in the higher temperature phase. The value must be in the range 0.0 to 1.0. Only valid for phase change elements, for all other elements the value is always zero. |
| Temperature | Array T(k) | Modify when argument KODE = 2See also Total Pressure entry in this table. |
| Total pressure | Array T(maxno+k) | Modify when argument KODE = 4
The total pressure of fluid element |