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Thermal Solver
Contains thermal solver related guides, such as the TMG reference manual, thermal API guide, and error message list.
Thermal solver reference
Describes the format and contents of the thermal solver's input and output files
Thermal solver input and output files
The thermal solver generates several data exchange files during the solve when using supported CAE software.
Thermal solver files
The thermal solver writes the following thermal solver files in the run directory during the solving process.
MODLCF
The MODLCF file is a condensed version of the MODLF file after addition of the Card 9 model parameters, element merging, substructuring, and combining of heat loads, capacitances, and conductances.

Thermal Solver
Contains thermal solver related guides, such as the TMG reference manual, thermal API guide, and error message list.
- Thermal solver guides
  Maya HTT's thermal solver is included in Simcenter 3D and in Simcenter Femap. This page contains links to thermal solver guides, which help you understand how the thermal solver works.
- Thermal solver reference
  Describes the format and contents of the thermal solver's input and output files
  - Introduction
    In most situations, a thermal model can be defined and solved directly within your CAE software. The thermal model is built using the software's interface, and the results can then be displayed and analyzed using its built-in post-processing tools.
  - Thermal solver input cards
    To access thermal solver features outside your CAE software, you must manually input instructions and data into the thermal solver’s input file also known as the data deck using any text editor.
  - Thermal solver input and output files
    The thermal solver generates several data exchange files during the solve when using supported CAE software.
    - Thermal solver flowchart
      This flowchart outlines steps and processes that the thermal solver uses to solve a thermal model using a supported CAE software.
    - Thermal solver files
      The thermal solver writes the following thermal solver files in the run directory during the solving process.
      - MODLF
        The MODLF file contains all the thermal couplings, radiative, conductive, hydraulic, and convective conductances, element capacitances, and heat loads calculated from elemental geometry and material and physical properties by the COND, GRAYB, VUFAC, and POWER modules.
      - MODLCF
        The MODLCF file is a condensed version of the MODLF file after addition of the Card 9 model parameters, element merging, substructuring, and combining of heat loads, capacitances, and conductances.
      - VUFF
        The VUFF file contains the model geometry elemental properties written by ECHOS, the view factors, heat flux view factors, solar view factors, albedo factors, and Earth view factors written by VUFAC, and the IR and solar spectrum gray body view factor matrices written by GRAYB.
  - Thermal solver modules
    The following table describes the thermal solver modules that are executed during the solving process. This section also consists of additional information about some of these modules.
  - Post-processing libraries
    The thermal solver provides the following post-processing libraries for generating results files.
  - Thermal solver bibliography
    The following bibliography lists all sources used to explain how the thermal solver works.
- Thermal solver theory
  Describes the theory and methods of the thermal solver.
- Thermal solver API
  Allows you to create or add functionality to enhance the thermal solver capabilities.
- Thermal solver error message list
  Lists solver messages that the thermal solver generates to communicate issues with the model or the solve.

MODLCF

The MODLCF file is a condensed version of the MODLF file after addition of the Card 9 model parameters, element merging, substructuring, and combining of heat loads, capacitances, and conductances.

The format of MODLCF is identical to that of MODLF, with the following exceptions:

For capacitances, VAL1 = capacitance value, VAL2 = 1 always.
MODLCF contains the additional capacitances, conductances, element sink temperatures, and heat loads specified on Card 9 XCOND, XCAP, SINK, and QNODE cards. The Card 9 XCOND 1WAYC conductance is written with the mnemonic 1WC, and the 1WAYR conductance is written with the mnemonic 1WR.
There is only a single RDF card present at the beginning of the file.
A series of time cards with MNM = TIM, VAL1 = time value are written at the end of the file. These contain the time values specified on Card 9 QNODE and Card 6e radiation heat load requests.
All elements in the model are assigned a capacitance value with a MNM = CAP card, which may be zero.
For merged elements follower conductances MNM = FOL are created, unless the Card 9 PARAMNOMRECOV option is specified.
Elements that have been eliminated with Card 8 and Card 9 PARAMSUBSTR substructuring and whose temperatures are to be calculated by the recovery process are set to be constant temperature sink elements MNM = SNK with a temperature of -1.E30.

Sink element temperatures

MNM = SNK

I = element

J = blank

VAL1 = temperature of the sink element

VAL2 = time when temperature occurs

Follower conductances

MNM = FOL

I = element whose temperature is to be followed

J = element whose temperature follows that of element I