Introducing boundary conditions

This topic explains the different types of boundary conditions used in turbomachinery simulations and how thermal, shared, and structural conditions are applied through simulation objects, constraints, and loads to represent multiphysics behavior.

This lesson may include hands-on exercises. Review the Discussion section for background information or click the button to proceed to the practical section.

Discussion

Turbomachinery simulations rely on multiple interacting physical phenomena, each represented through specific boundary conditions.

  • Convection boundary conditions capture heat transfer between fluids and solid components across main gas paths, cooling streams, cavities, and external flows.
  • Contact boundary conditions model thermal and mechanical interactions at interfaces such as joints, bolts, flanges, and mating surfaces.
  • Radiation boundary conditions account for radiative heat transfer from hot gas paths to surrounding components.
  • Structural boundary conditions represent loads, constraints, rotational effects, and deformation-driven behavior within the engine.
Boundary condition categories Thermal boundary conditions Shared boundary conditions Structural boundary conditions
Simulation objects
  • Duct Flow Boundary Conditions
  • Junction
  • Thermal Coupling
  • Thermal Deactivation Set
  • Immersed Ducts
  • Radiation
  • Edge-to-Edge Glue/Contact
  • Surface-to-Surface Glue/Contact
  • Cyclic Symmetry
  • Protective Layers
  • Structural Deactivation Set
Constraints
  • Temperature
  • N/A
  • User Defined Constraint
  • Manual Coupling
Loads
  • Thermal Stream
  • Thermal Void
  • Thermal Convecting Zone
  • Heat Generation (Thermal Loads)
  • Rotation
  • Gravity
  • Bolt Pre-Load
  • Force
  • Pressure

Hands-on material

To gain experience with the topics discussed here, complete the following:

Further learning