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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 theory
Describes the theory and methods of the thermal solver.
Radiation exchange methods
Thermal radiation is a heat transfer due to electromagnetic radiation emitted by the surface of bodies due to their temperature.
Basic view factor concepts
Understanding view factors

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 theory
  Describes the theory and methods of the thermal solver.
  - Introduction
    This guide provides the theory and methods used by the thermal solver, including methods to calculate conduction, convection, and radiation, as well as modeling specific topics using the thermal solver.
  - Conduction methods
    To model heat conduction, the thermal solver can use two finite volume methods, center of element method or element's center of gravity method, or the finite element method.
  - Convective heat transfer methods
    The thermal solver computes convection conductances for various geometrical configurations using correlations that depend on specified characteristic lengths, convective surfaces, and type of convection.
  - Radiation exchange methods
    Thermal radiation is a heat transfer due to electromagnetic radiation emitted by the surface of bodies due to their temperature.
    - Basic view factor concepts
      - View factor classifications
        Thermal solver view factors have three main classifications: view factors, orbital view factors, and heat flux view factors.
      - Understanding view factors
      - View factor sum
      - Orbital view factors
      - Supported element types
        Radiating elements may be defined with 1 to 4 corner nodes. The elements may be linear or parabolic.
      - Shadowing surfaces
      - Elemental subdivision algorithm
        For certain operations such as shadowing checks and ray-tracing elements need to be subdivided into sub-elements.
    - View factor calculation without ray-tracing
    - View factor calculation using ray-tracing
    - Plane stress view factor calculation when modeling with axisymetric or 3D elements
      This section explains how the thermal solver computes the view factor for axisymmetric or mixed 2D axi-3D models with plane stress elements for radiation requests.
  - Miscellaneous topics
  - References
- Thermal solver API guide
  Allows you to create or add functionality to enhance the thermal solver capabilities.

Understanding view factors

The view factor VF_ij from element i to element j is defined as the fraction of the radiation emitted by i that arrives at j without any intermediate diffuse reflections (but including specular reflections and transmissions), assuming perfectly diffuse and uniform emission in all directions. View factors are sub-classified into ray-traced and non-ray-traced view factors. Sometimes view factors are referred to as black body view factors (BBVF).

The non-ray-traced view factor is the view factor between the two elements if no specular reflection or transmission occurs. It depends solely upon the geometrical relationship between the two elements and the shadowing elements between them.

The ray-traced view factor is the view factor that also accounts for all specular reflections or transmissions between the two elements.

A heat flux view factor is a view factor to a diffuse radiative heat source of arbitrary shape.

An important view factor property is reciprocity:

VF_ij, VF_ji are the view factors from i to j and from j to i.
A_i, A_j are the areas of elements i and j.