Thermal Module Documentation

Module: src/fem/thermal Purpose: Index of documentation for BELFEM's thermal and magneto-thermal coupling module

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Overview

The thermal module builds the heat-conduction side of a coupled magneto-thermal problem. It is the counterpart of src/fem/maxwell. That module assembles the electromagnetic h-φ formulation; thermal assembles transient heat conduction and connects it to the electromagnetic solution. The field problem computes ohmic and hysteretic losses, which become the thermal heat source.

This module backs the coupled h-ɸ/T problem that belfem selects when a deck carries an unlabeled linear thermal or nonlinear thermal solver section; without one, the run is magnetic-only and this module is not built into the solve.

Key capabilities:

• Builds a thermal Kernel from an input.conf deck, either standalone on a mesh or coupled to an existing magnetic Kernel
• Assembles a transient heat conduction weak form specialized for the Maxwell coupling
• Builds the thermal boundary conditions from the input deck
• Provides element matrices for the h-formulation and the φ-formulation regions

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Key Classes

Class	Files	Role
ThermalFactory	cl_ThermalFactory.{hpp,cpp}	High-level orchestrator; builds the thermal kernel from an input deck
IWG_MaxwellThermal	cl_IWG_MaxwellThermal.{hpp,cpp}	Coupled weak form; derives from IWG_TransientHeatConduction
ThermalBoundaryConditionFactory	cl_ThermalBoundaryConditionFactory.{hpp,cpp}	Builds the thermal boundary conditions

Element matrices for the two formulation regions live in matrices/ (mt_thermal_h.{hpp,cpp}, mt_thermal_phi.{hpp,cpp}).

Entry Points

ThermalFactory has separate constructors for standalone and coupled setup:

ThermalFactory( const string & aInputFile, Mesh   * aMesh );            // standalone
ThermalFactory( const string & aInputFile, Kernel * aMagneticKernel );  // coupled

create_thermal_kernel() then returns the assembled kernel. Its consumer in the open-source tree is src/executables/belfem.cpp, which constructs the ThermalFactory and hands the thermal kernel to the controller only when the deck asks for the coupled problem. (src/executables/hphiTrun.cpp is the retired dedicated driver — the source is still present but is no longer built.)

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See Also

• Source code - header files in src/fem/thermal/
• Maxwell module - the electromagnetic half of the coupling
• IWG module - IWG_TransientHeatConduction, the base weak form
• Executables - belfem, which solves the coupled problem when the deck carries a thermal solver section

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Status: this index was written from the module's headers and its single consumer. The coupling itself — how the loss term is transferred and how the two kernels are stepped relative to one another — is not yet documented and deserves a usage guide of its own.