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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.
Miscellaneous topics
Heat flow calculation between groups B and A using the heat flows through groups
The heat flow between two groups is the sum of the following separate calculations: through directly connected conductances, through conductive conductances with the element CG method, and through Oppenheim radiative 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 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.
  - Miscellaneous topics
    - Heat flow calculation between groups B and A using the heat flows through groups
      The heat flow between two groups is the sum of the following separate calculations: through directly connected conductances, through conductive conductances with the element CG method, and through Oppenheim radiative conductances.
      - Heat flow between groups through direct conductances
        The heat flow between groups A and B via direct conductances is evaluated by summing the heat flow through all conductances connecting elements of group A and B directly.
      - Heat flow between adjacent groups using the element CG method
        The thermal solver evaluates the conductive heat flow between adjacent groups when the element CG conduction method is used by summing the heat flows across the boundary elements common to groups A and B.
      - Radiative heat flow between groups using Oppenheim method
        This topic explains the two-step process for calculating radiative heat flow between groups using the Oppenheim method, including the necessary equations and boundary conditions.
      - Accuracy issues with the calculation of equivalent conductances and ScriptFij
    - Heat pipe modeling
      Heat pipes transfer heat through the length of a heat pipe, from the evaporator to the condenser, by phase changing a working fluid. The condensed fluid is pumped back to the evaporator by the capillary force in the wick structure.
    - Automatically connected streams
    - Temperature error estimates
  - References
- Thermal solver API guide
  Allows you to create or add functionality to enhance the thermal solver capabilities.

Heat flow calculation between groups B and A using the heat flows through groups

The heat flow between two groups is the sum of the following separate calculations: through directly connected conductances, through conductive conductances with the element CG method, and through Oppenheim radiative conductances.

The thermal solver uses this calculation methodology when you request group to group heat flows for troubleshooting through reports or to calculate reduced models.

The following image shows the heat flow from elements of group B to elements of group A.

where:

Q_BA is the total heat flow from group B to group A through all conductances.
Q_directBA is the heat flow from group B to group A through conductances that connect the two groups directly. Examples of these are conductive couplings with the element center method, radiative conductances calculated using Gebhardt’s method, and thermal coupling.
Q_CONDBA is the heat flow from group B to group A through boundary elements connecting the two groups if the element CG method is used.
Q_RADBA is the heat flow from group B to group A through radiative conductances, if the Oppenheim method is used.