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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.
Thermal stream BC equations
The thermal solver models a one-sided thermal stream in thermal simulations using the energy balance equation.

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
- 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.
  - Elements in the thermal solver
    The thermal solver uses elements to calculate conductive, convective, and radiative conductances, as well as hydraulic resistances.
  - Supported element types for radiation
    Radiating elements may be defined with 1 to 4 corner nodes. The elements may be linear or parabolic.
  - 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.
    - Thermal stream BC equations
      The thermal solver models a one-sided thermal stream in thermal simulations using the energy balance equation.
    - Thermal void BC equations
      A thermal void represents a region in a thermal model where a fluid such as air or another gas is enclosed and interacts thermally with surrounding solid boundaries. This condition is used to simulate enclosed air pockets or cavities in thermal systems.
    - Convecting zone BC equations
      The thermal convecting zone boundary condition models a solid surface in contact with a fluid of known temperature and infinite heat capacity.
  - Radiation exchange
    Thermal radiation is a heat transfer due to electromagnetic radiation emitted by the surface of bodies due to their temperature.
  - Solar heating
  - Steady state analysis
    In a steady state analysis, the thermal solver solves the temperatures of non-sink elements iteratively using the following algorithm.
  - Transient analysis
    Transient analysis is performed using the following algorithm.
  - Hydraulic network analysis
    When the hydraulic pressure-flow network is present in the model, the thermal solver solves it at each iteration or time step using the following algorithm.
  - Miscellaneous topics
  - Thermal solver theory bibliography
    The following bibliography lists all sources used to explain how the thermal solver works.
- 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.

Thermal stream BC equations

The thermal solver models a one-sided thermal stream in thermal simulations using the energy balance equation.

A thermal stream defines convection due to fluid flow over surfaces, or over axisymmetric edges. The thermal solver internally creates 1D duct with mass flow elements on the selected regions and connects them to the nearest thermal solid elements through a convection thermal coupling.

The energy equation governing a one-sided thermal stream is given by:

Where:

m is the specified mass flow rate of the stream.
C_p is the specific heat of the stream fluid material.
T_f is the fluid temperature, computed by the thermal solver. In cases involving rotational effect, this fluid temperature can be expressed as a relative temperature.
T_s is the solid body temperature convecting with the stream, also computed by the solver.
A is the surface area of the solid body associated with the stream, computed by the solver. When the thermal stream is defined over axisymmetric edges, the thermal solver expands it in 3D to compute the area.
h is the specified heat transfer coefficient between the fluid and the solid surface.
H_p is the optionally specified heat pickup associated with the current element per unit area.

This equation models the transient thermal interaction between a flowing fluid and a solid surface, accounting for both convective heat transfer and additional heat pickup.

The thermal solver treats a specified two-sided thermal stream as two one-sided thermal streams in terms of heat transfer.

Applications

Thermal streams are used in simulations to:

Model the effect of a fluid such air or liquid coolant moving over or through a surface.
Represent the heat transfer effect of a fluid flow, simplifying the model instead of modeling full fluid domain.
Represent changing flow conditions in transient simulations.
Model electronics cooling, automotive engine systems, and HVAC applications.