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Rear linking tunnels for vehicle drag reduction

Drag ReductionPassive DragPassive Flow ControlRear Linking TunnelsSustainable mobilityVehicle Aerodynamics


An innovative method to reduce a vehicle’s aerodynamic resistance through novel automotive design and passive drag reduction devices. This passive flow control is achieved by adding linking tunnels at the rear of the car.

Technical features

The innovation consists in amplifying the effect of the passive flow control for a ground vehicle with the aim of drag reduction. Adding specific paths between high-pressure sidewalls and low-pressure wake zone through linking tunnels is the main concept of this passive flow control. The main reason for the drag reduction is the pressure recovery on the rear vertical surface of the model near the wake zone due to high-pressure blowing flow through the linking tunnels. The noticeable drag reduction with a small modification in the base model in comparison with other passive methods makes this design effective and creates some great potential for the combination of this passive method with other available active methods.

Possible Applications

  • Rear car bodywork parts;
  • Fuel-based road cars;
  • Electric and hybrid cars;
  • Industrial automotive sector;
  • Super and hyper cars;
  • Motorsport racing series;


  • Drag Reduction and Improved Aerodynamic Efficiency;
  • Fuel Saving and Improved Mileage;
  • Reduction of Air Pollution;
  • Innovative tail-light design;
  • No negative effect on the aesthetic aspects of the cars’ design;
  • The efficiency of this passive flow control will increase by an increase in the number of modules;