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Thermal Boundaries

PyExtrusion 0.19.0 exposes three distinct thermal tool families. They must not be combined into a claim that the package predicts production exit temperature.

Stüwe analytical estimate

The Python API uses the ASCII spelling stuwe_*. The Stüwe model implemented by stuwe_surface_exit_temperature_estimate() is a limited three-component analytical surface-temperature estimate reproduced by Sheppard.

It is not a transient temperature field and does not explicitly represent all container, die, tooling, porthole or temperature-dependent material effects.

Saha local source terms

The saha_* functions expose local heat-generation or heat-flux source terms for:

  • deformation;
  • billet-container friction;
  • dead-metal-zone friction;
  • die-bearing friction.

These functions do not integrate a temperature field. A transient heat balance, geometry, heat partition and complete boundary conditions would still be required to calculate temperatures.

Sheppard Eq. 2.25

sheppard_billet_container_interface_temperature_c() evaluates the stated billet/tooling interface-temperature relationship using the supplied body temperatures and thermal properties. It does not define how newly generated friction heat is partitioned between aluminium and tooling.

Explicitly outside the model

PyExtrusion does not currently:

  • provide a production-grade exit-temperature predictor;
  • reconstruct an Integral Profile temperature field;
  • reconstruct Saha's complete finite-difference solution;
  • invent missing boundary conditions;
  • infer source-exact friction-heat partition;
  • model complete transient heat storage in billet, container, die or tooling.

See the Engineering API for runnable calls that keep these three result types separate.