Aerodynamics

In designing and developing products reliant on precision aerodynamics, the challenge facing research and development teams is very often the flow field and its impact on the item being developed. The effect on the flow field is often the result of concentrated vortices that are shed from a surface, propagated through the flow field, and convected past another surface.

Examples of this are:

  • Fixed wings where shed vortices cause turbulence which may interfere with a trailing aircraft
  • Helicopters, where vortices shed by each rotor blade convects close to the other blades and the helicopter body
  • Automobiles, where shed vortices increase drag, create noise and decrease the vehicle performance
  • Wind mills, where shed vortices effect the power production
  • Bicycles, where the shed vortices affect drag and performance
  • Cases involving ship/aircraft operations, parachutes, gliders, cooling fans
Simulation of such effects is important in wing design, blade design for helicopters/wind turbines/fans, developing operating limits of helicopters landing/taking off on ships, aerodynamic testing of cars, trucks, computing wind resistance for bicycles, body design of race cars.

Vorticity Confinement (VC), Flow Analysis’ state-of-the-art models, can be used to compute detailed wake effects in the areas aforementioned. In particular, this includes fluctuations due to individual tip vortices and shed vortex sheets. An important consideration is that no input involving the wake geometry be required as part of the computation. Wakes, a very important aspect of aerodynamics, cannot be computed easily within engineering time constraints and with the engineering methods now in common use. However, VC overcomes these inherent difficulties.

Specific examples where the critical knowledge of the unsteady wake include:

Fixed wing aircraft

  1. Wing design (aerodynamic testing) - includes testing with devices, such as slats, slots, flaps, and spoilers affixed to a simple wing.
  2. Vibratory loading due to shed vorticity impingement on aircraft.
  3. Wake Turbulence

Rotorcraft/Helicopters

  1. Blade design – Aerodynamic testing of blades
  2. Blade loading in hover (including body)
  3. BVI (Blade vortex interaction)
  4. Interaction of the tail rotor with the main vortex following quick turns on deck
  5. Interaction of another landing helicopter with a wake
  6. Ability of ground personnel to walk in the strongly fluctuating wake near the ground caused by shed individual vortices.
  7. Sand/snow pickup due to the individual shed vortices (brownout, whiteout)
  8. Vibratory airloads caused by individual blade vortices impinging on the fuselage
  9. Effects of vortices on operations such as crop dusting

Other

  1. Aerodynamic testing – optimization of automobile body design
  2. Air flow in automobile and aircraft cabins for passenger comfort studies
  3. Streamlining race cars
  4. Drag reduction for bicycles and automobiles
  5. Body design to reduce wind resistance and increase performance for bicycles
  6. Aerodynamic testing of parachutes, Gliders etc.
  7. Aerodynamic testing of cooling fans
  8. Effectiveness on cooling for building interiors, engine compartments, computer cabinets etc.
  9. Flow simulation for aircraft landing/take off on ships

Related Videos