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Setup
Prepare your model and run the simulation.
Aerodynamic and Aeroacoustic Setup
Prepare your model for wind tunnel analysis using ultraFluidX.
Prepare the Model
Set up the wind tunnel and prepare the aerodynamics and parameters of your model.
Define Wind Tunnel
Use the Edit Tunnel tool to define the size of the wind tunnel.

Welcome
What's New
View new features for HyperMesh CFD 2026.
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 Repair
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.
- Aerodynamic and Aeroacoustic Setup
  Prepare your model for wind tunnel analysis using ultraFluidX.
  - Transfer Data
    After preparing your model, use the Data Transfer tool to transfer mesh data to the environment used for aerodynamic and aeroacoustic setup.
  - Parts and Assemblies
    Manage the parts and assemblies that make up your model.
  - Prepare the Model
    Set up the wind tunnel and prepare the aerodynamics and parameters of your model.
    - Define the Unit System
      You can change the unit system using the Unit System Selector or the Preferences. When importing "discrete mesh" files (.stl, .nas, .fem) with unspecified units, select the model unit in the Import Options dialog.
    - Create Coordinate Systems and Align Parts
      Use the Systems tool to define local coordinate systems and translate the parts needed to align the model.
    - Define Wind Tunnel
      Use the Edit Tunnel tool to define the size of the wind tunnel.
    - Define Turbulence Source Regions
      Use the Turbulence tool to generate turbulence source regions.
    - Position the Car
      Use the Move tool to position the car inside of the wind tunnel.
    - Identify Parts
      Use the Identify Parts tool to define types of parts like wheels, heat exchangers or body panels, which require specific modeling techniques for the CFD run.
    - Part Properties
      Selecting a part allows you to set values for various properties.
    - Adjust Ride Height
      Use the Ride Height tool to adjust the heave, pitch, and roll of the model.
    - Adjust Part Normals
      Use the Normals tool to identify and correct the surface normal directions on parts.
    - Define the Mesh Controls
      Use the Mesh Controls tool to define regions with a user-defined volume element size.
    - Define Fluid Materials
      Use the Material tool to define a fluid material for the wind tunnel.
    - Define the Belt System
      Use the Belt System tool to model a belt system.
    - Define the Output Controls
      Use the Output tool to create output controls.
  - Analysis
    Submit jobs and view reports.
Post-Processing
Post-process the simulation results by creating visualizations and measurements.
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.
Automation
Automate simulation processes with templates and utility scripts.
Solver Help
More resources for AcuSolve and ultraFluidX solvers.

View All Altair HyperWorks Help

Define Wind Tunnel

Use the Edit Tunnel tool to define the size of the wind tunnel.

From the Setup ribbon, click the Edit Tunnel tool.

Figure 1.
Edit the wind tunnel's height, width, and length in the microdialogs that appear in the modeling window.

Figure 2.
Edit the inflow velocity and tunnel extent properties in the modeling window.

Tip: You can also define inflow velocity by double-clicking the large arrow at the bottom of the tunnel and entering a value in the microdialog.
Optional: Select the boundary layer suction line in the modeling window and turn the boundary layer suction off in the microdialog.
Optional: Select the boundary layer suction line in the modeling window and define the location reference in the microdialog.
Edit the boundary layer suction by selecting the boundary layer suction line in the modeling window and completing one of the following:
- Enter a distance value in the microdialog.
Figure 3.
- Click in the microdialog and drag the boundary layer suction line.
Figure 4.
Optional: Define Ground Configuration properties (among others) in the Property Editor panel.
1. Define ground configuration properties, including:
  - Enable BL (boundary layer) Suction.
    - Location reference.
    - Distance.
  - Enable Ground Patch: Create a finite ground patch with a no-slip boundary condition around the car instead of the entire wind tunnel floor.
    Note: When a ground patch is enabled, it will become visible in the model window.
  - Length: sets the length of the ground patch behind the car as a ratio of the car's length.
  - Width: sets the width of the ground patch on either side of the car as a ratio of the car's width.
  Figure 5.
Optional: Configure thermal properties in the Temperature BC section of the Property Editor.

Note: Activate thermal functionality by enabling Thermal Model in the Run dialog.
1. Define the Inlet temperature.
2. Select a BC Type (boundary condition), between Adiabatic and Temperature. If Temperature, define the temperature.
3. Engage inlet or outlet Absorbing BC. This absorbs pressure fluctuations through the boundaries, reducing transients.