Home
Setup
Prepare your model and run the simulation.
General Setup
Prepare your model for a general AcuSolve simulation.
Radiation
Define radiation conditions and create emissivity models.
Thermal Radiation
Define thermal radiation conditions.
Define External Radiation
Use the External tool to apply external radiation heat transfer to selected surfaces or thin solids.

Welcome
What's New
View new features for HyperMesh CFD 2024.1.
Get Started
Learn the basics and discover the workspace.
Onboarding Resources
Discover HyperMesh CFD functionality with interactive tutorials and community resources.
Solution Layers
Solution-centric workflows allow you to traverse through modeling environments using a dedicated UI layer.
Manage Files and Data
Create, open, import, and save models.
Convert
Use the Convert tool to convert entire models between data types.
Geometry Modeling
Manage CAD, FE, and 2D parametric sketch geometry.
Meshing
Generate surface/volume mesh by defining mesh controls, or interactively create and edit 2D surface mesh.
Setup
Prepare your model and run the simulation.
- General Setup
  Prepare your model for a general AcuSolve simulation.
  - Flow
    Set up the simulation model, materials, domains, and boundaries.
  - Radiation
    Define radiation conditions and create emissivity models.
    - Thermal Radiation
      Define thermal radiation conditions.
      - Set Up the Thermal Radiation Settings
        Use the Physics tool to turn on thermal radiation physics and define the thermal radiation settings used in the simulation.
      - Define Surface Finish Models
        Use the Surface Finish Library tool to create, delete, and import/export surface finish models. A surface finish definition is an ideal grey-surface emissivity model used in the radiation equation.
      - Define Default Surface Conditions
        Use the Defaults tool to define global surface conditions for thermal radiation.
      - Assign Surface Finishes
        Use the Surface Finish tool to apply surface finish properties to selected surfaces.
      - Define External Radiation
        Use the External tool to apply external radiation heat transfer to selected surfaces or thin solids.
      - Define Radiation at Openings
        Use the Opening tool to apply radiation boundary conditions at openings. A radiation opening definition provides a method of fully enclosing a fluid domain that is not surrounded by walls. This condition is appropriate for inlet and outlet type boundary surfaces.
      - Define Radiation Output
        Use the Output tool to apply radiation output settings to selected surfaces.
    - Participating Media
      Define participating media radiation conditions.
    - Solar Radiation
      Define solar radiation conditions.
  - Motion
    Define direct, derived, and constrained mesh motion.
  - Solution
    Define output conditions, run the simulation, and view the results.
  - AcuTrace
    AcuTrace is particle tracer that runs as a post-processor to AcuSolve.
- Aerodynamic and Aeroacoustic Setup
  Prepare your model for wind tunnel analysis using ultraFluidX.
Post-Processing
Post-process the simulation results by creating visualizations and measurements.
Automation
Automate simulation processes with templates and utility scripts.
Design Exploration
Once the baseline model is prepared, you can define morph volumes, morph geometry, create design shapes and run DOE studies. These tool work for both AcuSolve and ultraFluidX-based workflows.
Solver Help
More resources for AcuSolve and ultraFluidX solvers.

View All Altair HyperWorks Help

Define External Radiation

Use the External tool to apply external radiation heat transfer to selected surfaces or thin solids.

From the Radiation ribbon, click the External tool.

Figure 1.

Select the surfaces or thin solids on which to apply the radiation heat transfer.

To Select

Do This

Surfaces

Set the guide bar selector to Surfaces.
Select surfaces.

Thin Solids

Change the guide bar selector to Thin Solids.
Select thin solids.
Note: You can only select thin solids if layers have been defined using the Thin tool.
Select a direction option from the guide bar.
- Direction: Away from Parent Surface - Define the condition on the boundary surface furthest from the parent surface.
- Direction: Adjacent to Parent Surface - Define the condition on the boundary surface closest to the parent surface.
- Direction: Both Sides - Define the condition on both sides of the boundary surface.

An external radiation dialog opens.

Select an external radiation definition from the drop-down menu and define radiation properties.

Option	Description
Zero	Enter a reference temperature value.
Constant	Enter a reference temperature and flux value.
Piecewise Linear and Cubic Spline	Enter a reference temperature value, define the x-axis using the Curve fit variable drop-down menu, then use the table and the plot area to define the radiation.

From the guide bar, execute the command in the following ways:
- Click to confirm your selection and remain in the tool.
  This allows you to continue creating instances and helps you visualize and edit instances with the legend.
- Click to confirm your selection and exit the tool.