This chapter contains an overview of the resolution setup for various types of vehicles in ultraFluidX. These best practices have been derived using industry standard/public models, as well as client project experience. Best practices are reviewed and improved with every release. For an overview on ultraFluidX and the requirements needed to run the solver, please refer to the Altair ultraFluidX 2021.2 User Guide.

The current guide includes:

  • Wind Tunnel Setup
    • Tunnel definition and floor boundary conditions
    • Domain size and blockage ratio
    • Inflow Mach number and run time
  • Refinement Strategy for Passenger Vehicles
    • Box refinement zones
    • Offset refinement zones
    • Custom refinement zones
    • Recommendations for certain boundary conditions
      • Wheels
      • Porous media
      • Belts and tunnel suction resolution
  • Strategy for large-eddy simulations
    • Wall model variants
    • Turbulence generators
  • Considerations for specific vehicle types
    • Considerations for hatchbacks/compacts/estates
    • Considerations for sedans/coupes/fastbacks
    • Considerations for SUVs/pickup trucks/vans
  • Refinement Strategy for Commercial Heavy Trucks
    • Cab-over
    • Long-nose

The best practices presented in this chapter are vehicle-type-dependent. In the first sections focus on passenger cars, then motorcycles and commercial trucks in separate sections. For passenger cars, methods for sedan-like vehicles with a slanted roof, hatchback-like vehicles with a defined separation edge, and larger vehicles (SUVs, vans, and so on) are noted. For commercial trucks, this guide notes different tractor design types (cab-over, long-nose) and how to handle them.