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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 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.
Comparison of view factor computation modules
This page compares VFRTGPU to the HEMIVIEW and VUFAC modules.

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 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.
    - ANS2TMG module information
      ANS2TMG translates Ansys models into thermal solver input files by merging Ansys and thermal solver data, creating necessary boundary conditions, and converting thermal elements and material properties.
    - GRAYB module information
      The GRAYB module crates the radiative conductances, the IR, solar spectrum, and gray body view factor matrices.
    - HEMIVIEW module information
      The HEMIVIEW module calculates diffuse blackbody view factors using the hemicube method, which allows computer graphics hardware to accelerate the calculations.
    - MEREL module information
      The MEREL module performers the model condensation by element merging or renumbering, automatic combination, substructuring, and model thinning.
    - NEVADA module information
      The NEVADA module converts a NEVADA input deck into an equivalent I-deas Universal file.
    - POWER module information
      The POWER module calculates IR and solar spectrum radiative heat loads from the orbital view factors, heat flux view factors, and view factors of the VUFF file.
    - REFORM module information
      The REFORM module transforms the conductance-capacitance model from the MODLCF file into SINDA or ESATAN formats, or the geometry model into TRASYS or NEVADA formats. The formatted models are written in the FMODLF file.
    - TMG2ANS module information
      The TMG2ANS module translates the TMG node temperature results from GTEMPF to ANSYS version 5 input files.
    - VUFAC module information
      The VUFAC module calculates view factors, orbital view factors (solar view factors, albedo view factors, Earth view factors), heat flux view factors, view factor for axisymmetric modeling with plane stress, and thermal couplings.
    - Comparison of view factor computation modules
      This page compares VFRTGPU to the HEMIVIEW and VUFAC modules.
    - Comparison between CONDN and COND modules
      The following list provides a brief comparison between the COND and CONDN conduction 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.

Comparison of view factor computation modules

This page compares VFRTGPU to the HEMIVIEW and VUFAC modules.

VUFAC module: Computes the ray-traced, non-ray-traced, and other types of view factors, using machine's central processing unit (CPU). The VUFAC module calculates view factors with a combination of the contour integration and Nusselt sphere methods, using automatic elemental subdivision algorithm when shadowing occurs. View factors between elements are calculated one at a time. If shadowing occurs, the number of calculations required to compute the view factors varies roughly as the cube of the number of elements, which is very CPU intensive. Depending on the type you select, and number of view factors calculated by the solver, the view factor computations can be CPU intensive using the VUFAC module.
HEMIVIEW module: Uses the machine's graphics card in conjunction with the open graphics library (OGL) to compute the blackbody view factors using an imaginary hemicube. The HEMIVIEW module is much faster. It uses computer graphics techniques to graphically render the radiating elements onto the five sides of a hemicube (a half-cube) placed at the CG of an element, called the emitting element. The view factors from the emitting element to the other elements, called the receiving elements, are determined by post-processing the graphical images of the receiving elements projected onto each of the hemicube sides. The hemicube method is fast for two reasons: the number of renderings is linearly proportional to the number of elements, and the rendering calculations are performed with specialized fast graphics cards. The accuracy and computation time of the hemicube method is limited by the pixel resolution of the drawing area. However, it only supports blackbody view factors.
VFRTGPU module: Uses the Monte Carlo method to compute both the blackbody view factor and ray-traced radiative conductances using the machine's graphics processing unit (GPU). Depending on the number of radiative conductances that are computed in a radiation simulation, the GPU-based Monte Carlo method can perform approximately an order of magnitude faster on a supported GPU hardware compared to the other modules that compute the same amount of radiative conductance. In ray-tracing, many rays are randomly cast between elements participating in the radiative exchange. The rays follow the path taken by the radiation. The software launches several rays from each element using the Monte Carlo method.