Thursday, October 14, 2004

Aerodynamics of Formula One (F1)

In modern Formula One (F1), aerodynamics are the field in which the biggest steps forward in performance are to be made. Ever since the introduction of the first wings by Lotus and Ferrari in the 1960s, what was formerly a hit and miss technique has evolved into a near-exact science. Every square centimetre of today's cars is carefully honed to optimise airflow. The basic equation engineers face is simple: to inverse the physical principle that enables a plane to stay airborne.

The work of aerodynamicists is to find downforce – the vertical force that pushes cars to the ground by forming a zone of low pressure underneath its wings – and to minimise drag, the associated longitudinal force that resists the car's forward movement. The performance of any single-seater car is a function of this inevitable standoff. Accordingly, engineers have become obsessed with the tiniest of details, and that's no surprise when you consider that a nosecone-mounted aerial with an excessively big diameter can cost the equivalent of around 10bhp in engine power. Yet this spectacular example does not mean that Formula 1 cars are profiled like razor-sharp arrows. On the contrary. Their large, exposed wheels produce turbulence that makes them as about as aerodynamic as a tank. The drag coefficient of an everyday Clio is much lower… but a Clio generates significantly less downforce. Launched at full song at 250kph, a Formula 1 car benefits from more than a tonne of aerodynamic load.

Over the past thirty years or so, engineers haven't left a single stone unturned in their quest for downforce. Successive inventions such as fan cars, skirts, so-called side pod-mounted penguin flaps, vanes on engine covers or deformable body components that flex at speed all brought spectacular performance gains before leading the sport's governing body to step in. Today's regulations mean that aerodynamicists must work within a restrictive, strictly pegged out framework. The most recent rule changes introduced before the start of the 2001 season dictated an increase of 50mm in front wing height and a maximum limit to the number of elements that can make up rear wing. When the regulations are stable, however, engineers are capable of finding between 5% and 10% extra downforce each year, a rule of thumb that applies equally to the Renault F1 Team. Outwardly, the R202 might seem very similar to its predecessor, the B201, yet the efficiency of its aerodynamic package has progressed significantly. And so, in turn, has its performance.

Aerodynamics are just as fundamental for the drivers. In the same way that an airplane is not able to take off in the immediate wake of another, it is not possible for two single-seater cars to follow each other too closely through a corner because of the turbulence produced by the leading car. The risk for the second car is quite simply sliding off the track. Along straights, however, it is possible for the chasing car to benefit from the slipstream of the one in front, a phenomenon that can facilitate overtaking.

Finally, the efficiency of an aerodynamic package is only revealed at full song since downforce increases exponentially with speed. Ironically, a corner that may not be particularly difficult at 250kph can pose a problem at 180kph. Aerodynamics and driver bravery are intimately intertwined.

Two years ago, aerodynamics were the principal shortcoming of the Benetton team. Today, this department has been significantly reinforced since the arrival of Mike Gascoyne as Technical Director. A staff of over forty currently works on Renault F1 Team's aerodynamics programme under the leadership of John Iley. Although the way it is organised may not be unique to Enstone, it is worth highlighting all the same, its most notable feature being the fact that two distinct shifts work out of the team's ultra-modern wind tunnel facilities. "Competition in F1 today is such that our wind tunnel functions 17 hours a day," explains John Iley. "It's impossible to get our engineers to work that long! So we have decided to split the staff into two teams. Each shift is independent and is given a precise programme to work on." Doesn't that run the risk of creating rivalry between the two? "I wouldn't call it rivalry. More a sort of emulation. Each one wants to outdo the other," smiles Iley. "And that can only be beneficial for results."

The engineers give their maximum but they also have a free reign as far as their research goes. Having said that, many of their ideas never get used. Less than 20% of the aerodynamic solutions examined actually ever find their way on to the race car. That doesn't mean the engineers aren't up to the job; it's just that every avenue is considered to be worth exploring. "The technical regulations are so restrictive today that it is no longer possible to make a single major stride forward. We progress bit by bit in all areas, which means it's the teams with the biggest budgets and best infrastructures that have the edge," underlines Head of Aerodynamics John Iley. Certain teams are effectively thinking in terms of a second wind tunnel to function in parallel to the first and there is already talk of annual aerodynamics research programmes based on 5,000 hours of wind tunnel time. At Renault F1 Team, the plan is to introduce regular modifications to the R202 as the season progresses. Even as early as the second Grand Prix of the year, at Sepang, the cars featured a new rear wing and a new extractor.

There is little to be gained from spying. "Each car has to be considered as a complete package," comments Iley. "What works for one team doesn't necessarily work for everyone. Obviously, we all observe what everybody else is up to, and if an idea proves effective it will always turn up sooner or later on all the cars."

And what about looks? Here again, aesthetics tend not to weight heavily in the balance. Efficiency is all that counts. "A car that wins is always beautiful", quips John Iley. "OK, if two solutions produce identical results, then we will go for the most stylish solution, but such cases are rare."

Although Formula 1 cars obey precise physical laws, they cannot take their inspiration from nature, despite the temptation to look at windswept landscapes or the fins and wings of certain animals. "It's true that an organ is dictated by its function and there could be something to be gained from looking at nature," smiles John Iley. "Unfortunately, nature doesn't have to work to Formula 1's technical regulations…" Pity!

In principle the aerodynamic design has to take three things into account; Down force, suction and airflow. To produce down force and suction, the airflow has to be optimized around and under the car. The effectiveness of the down force is measured by the 'weight' that the airflow produces on the car. The amount of pressure that is produced is so great that, at approximately 250 KMH, an F1 racecar could drive inverted on the ceiling. The extremely fast air under the car is used to create a vacuum that, in addition to the down force, sucks the car onto the track.

More information:
http://www.f1technical.net/article10.html

5 Comments:

At 9:32 AM, Blogger . : A : . said...

Thanks for visiting and thanks for this informative post.

 
At 5:31 PM, Blogger delon said...

You're welcome.

Regards,
Erwin

 
At 6:57 AM, Blogger unixlinux said...

Nice KDE rlated blog. Visit my 61xbr950 kde sony blog.

 
At 3:55 AM, Blogger Plasma TElevision Center said...

Hi thanks for your blog, I liked it! I also have a blog/site about Plasma Television that covers Plasma Television related stuff. Please feel free to visit.

 
At 3:56 AM, Blogger TadaDiscounts said...

You have an awesome site here! I have a website that may interest you- candles with get content such as- candles

 

Post a Comment

<< Home