F1 Fanatic guest writer John Beamer continues his technical analysis of the 2009 F1 cars with a look at the mid-section of this year’s designs.
When comparing a 2008 and 2009 F1 car the wider front wing and squashed rear wing are the most dramatic changes. Look closely again and one can see equally striking changes in the mid-region.
The new technical regulations vastly restrict the deployment of bargeboards and podwings. Boards were pioneered by McLaren in the early 1990s to manage airflow to the diffuser and around the sidepods. The airflow interactions are complex and involve the creation of many vortices to steer the flow under and around the floor.
Podwings are outgrowths of the sidepod bodywork and were initially developed by the old BAR team in 2005. They condition turbulent flow from the front wheels, calm it and funnel it to the rear wing giving more consistent performance (e.g., when cornering).
Last year BMW were the first team to integrate the devices, often with the axe-head (the section of floor jutting out ahead of the sidepod).
The 2009 regulations were designed to eliminate bargeboards/podwings and although the plethora of turning vanes that used to adorn a car has disappeared, the rule-makers haven?óÔé¼Ôäót been wholly successful as teams are still running smaller devices.
How did this happen?
The regulations specify a restricted area, which means there is only a very small zone close to the monocoque where a bargeboard is permissible. In addition the FIA specified that bodywork around the sidepods must meet minimum radii requirements, although there is some freedom at the front of the pods where the impact structure terminates. Many commentators, including me, thought that bargeboards and podwings would disappear but teams have been creative in their interpretation of the regulations.
Nearly all teams have adopted some form of bargeboards. Although they are more angular, smaller and less effective than in years gone by, their ubiquity suggests a significant performance gain which is magnified by the banning of more forward turning vanes. Given the tight design cycles there isn?óÔé¼Ôäót a lot of variance (yet) in size and shape of the designs. Over the season expect flicks and saw-tooth edges to proliferate as teams optimise aero performance ?óÔé¼ÔÇ£ a close look at the BMW boards shows a small fin on the top edge.
Deploying podwings was a little more controversial as teams must interpret the language in article 3.8.6, which defines what bodywork must be enclosed by the side-impact structure. There is a small zone ahead of the sidepods where bodywork can be deployed. In addition some team (notably Ferrari) have shortened the and adapted the sidepod fronts to give more space to deploy podwings. At this point almost all the teams have the devices ?óÔé¼ÔÇ£ Brawn GP excepted – although McLaren, Williams and Renault only adopted them recently. By 2010 these loopholes may be closed.
Among the teams that use pod wings there are different interpretations. Ferrari?óÔé¼Ôäós rise from the floor, jut some way forward and house the mirror. They also have a slit for calming some of the air that is disturbed by the tyres ?óÔé¼ÔÇ£ the slit allows high pressure air to bleed through reducing air vorticity. Other teams, like Force India, have managed to design more conventional pod wings that form a close section with the axe-head. By the time the F1 circus returns to Europe expect an even greater variety of pod wing and barge board design.
Pod wings and barge boards aside, the most notable change in the car?óÔé¼Ôäós mid-regions is the absence of all other fins and flick-ups. As such the new cars look much sleeker than their 2008 counterparts. The FIA hopes that will create close racing.
In just over a week?óÔé¼Ôäós time we should find out.
For a complete exposition of podwings and bargeboards read my article in issue 8 of Bernoulli Aerodynamics International.
Read more: F1 2009 technology: front wing