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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.
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.
Multiple convective boundary conditions on the same selection
This section describes how the thermal solver calculates convective heat flow and post-processing outputs when multiple convective boundary conditions are applied on the same geometric selection.

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.
    - Free convection correlations
      Free or natural convection occurs when the heat is transferred between convective surfaces and a moving fluid, in which the fluid motion is not induced by an external force.
    - Across gap convection correlations
    - Forced convection correlations
    - Multiple convective boundary conditions on the same selection
      This section describes how the thermal solver calculates convective heat flow and post-processing outputs when multiple convective boundary conditions are applied on the same geometric selection.
  - 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
  - References
- Thermal solver API guide
  Allows you to create or add functionality to enhance the thermal solver capabilities.

Multiple convective boundary conditions on the same selection

This section describes how the thermal solver calculates convective heat flow and post-processing outputs when multiple convective boundary conditions are applied on the same geometric selection.

The total convective heat flow on an element, denoted as i, is the sum of contributions from various boundary conditions (BC), labeled as b. Each BC may have multiple fluid elements, j, connected to i through convective conductances G_ij:

where T_i and T_j are temperatures for the solid element i and fluid element j, respectively.

The convective heat flow contribution from each BC can also be expressed as:

where:

h is the input heat transfer coefficient (HTC) of the BC.
A is the area of the BC.
C is the area correction factor.
T_i^(fb) is the fluid temperature for element i from BC b.

To align with the first equation, the following relationships are established:

In post-processing for a single BC, the output convection coefficient is given by:

and the area corrected convection coefficient is:

When dealing with multiple BCs, the objective is to average h, A, and C such that:

The averaged values are used in post-processing outputs, with h_i as the convective flux output, h_i C_i as the area corrected convective flux output, and C_i as the area correction factor. The averaged fluid temperature is calculated as:

So that, the convective heat flow for element i is:

The averaged area A_i is defined as:

This indicates that the area corrected HTC is the sum of the area corrected HTCs from the contributing BCs:

The averaged area correction factor is then defined as:

Which leads to the HTC being the sum of the HTCs from the contributing boundary conditions.