15 Sep 2016
September 15, 2016

The return of the fan car…

On Wednesday 14th September during LCV 2016 (Low Carbon Vehicle Show) at Millbrook Proving Ground a new fan car was born, the AERO-P Atom.  The vehicle is part of an ongoing collaboration between TotalSim, Ariel Motor Company and Delta Motorsport after an R&D grant from the Niche Vehicle Network.

The car is a modern take on the fan cars of the past such as the Gordon Murray Brabham BT46 of 1978.

The modern fan car tackles three desirable characteristics that traditional aerodynamics cannot achieve in unison.

Downforce at Zero Speed – This helps with traction, braking and low speed cornering, where traditional aerodynamics cannot function due to the lack of speed to create downforce.

Downforce with little or no drag increase – The ability to create downforce with little or no increase in drag helps reduce CO2 emissions and reduces laptime.

Downforce on demand – The ability to create downforce on demand and then switch it back off again helps make the modern fan car safer and more stable.


Although much of the project is still in development and remains confidential, an interesting demonstrable output is the Atom test car giving downforce at any speed, including standstill.  Below is a sneak preview of the performance it is capable of.

The blue diamond is the baseline car.  By adding a traditional wing package we can increase downforce (at speed) to ~900N with the associated drag penalty, shown by the red square.

The green triangle shows some of the potential of the fan car, generating over 1600N of Downforce with no drag penalty!

Fan Car Peformance

Although it’s a large and complex project, covering a lot of areas, performance is core to us.  We’re moving towards the point where traction and therefore acceleration, particularly from standstill, are limited by mechanical grip so we’re trying to come up with ways of overcoming this.  One of our targets was to minimise or remove the need for aerofoils and have ‘downforce when stationary’.  Inspiration came from banned racing cars of the past, so there’s a big nod from us to Jim Hall’s 1970 Chaparall 2J Sucker Car and the Gordon Murray Brabham BT46B Fan Car of 1978.  The Atom test car has already been nicknamed The Vacuum Cleaner and hopefully it follows in the tradition of these two great cars.” Simon Saunders, Director of Ariel

On the AERO-P Atom there are no aerofoils.

Powered by two small, lightweight, high speed fans the Atom test car has an additional moulding and rubber skirts added to the bottom of the tub as well as ducting and a standalone battery pack.  The ability to spin up the fans very quickly allows the system to be turned on and off when required, whether under acceleration, cornering or braking, either manually or automatically. The fans are therefore only running for brief amounts of time, for instance from start, when cornering or under braking.  When not required at cruise and high speed conditions the system remains in stand-by, improving vehicle range and reducing CO2 emissions.

When the system is turned on the car visibly squats on the ground so you can see it working, which is pretty exciting,” said Simon Saunders, Director Ariel Motor Company.

The aerodynamic development on the project was carried out by TotalSim.

Fan car developed in CFD by TotalSim

The image above shows the low pressure under the bodywork is sealed by the skirts. The car was developed in CFD by TotalSim.

  “The ability to create significant downforce at zero speed is very exciting.”  Rob Lewis, Managing Director TotalSim.

Simulated performance times and bench testing of AERO-P prototypes at full size were carried out by Delta Motorsport, based at Silverstone.

We love working with creative, lateral-thinking businesses such as Ariel and TotalSim, coming up with – and then implementing – novel solutions to tricky problems. As with many of the projects we’re working on today, we see the trickle down from high-performance vehicles to conventional passenger cars over time, so it’s great to be ahead of the curve with these new technologies.” Nick Carpenter, Engineering Director of Delta Motorsport.

The project was supported by Innovate UK via the Niche Vehicle Network and their annual R&D Competition. 

Further development of the concept is still ongoing. Watch this space!

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