Jaguar Barge Boards Gone!

[desmo]

Jaguar this season have been running huge Mac-style barge boards. Well look at these pics of JH's Jag from friday practice at Hockenheim:








BAR have ballyhooed recent aero mods and no matter how closely I examine photos before and after the "major" aero revisions on their cars, I can find no visible changes. Now this from Jaguar without a word! Surely this is a response to the low downforce set-up for this rather unique circuit. Or is it?

[bobdrummond]

I think it was last year that Williams were testing at Silverstone when a barge board fell off Schumachers car. He didn't notice any loss of downforce and the 'boards were removed altogether.
Perhaps when minimising drag is paramount, removing them helps the aero.

Great photos, by the way.

[THR]

Nice spot

the barge boards must create drag of some sort, downforce doesnt come for free and if u create it by adding bardge borads, if u take them off the drag will reduce.

[Dino IV]

Hmmm ... that's strange. I thought the theory behind barge boards was to just leave room for a certain clean flow of air through into the radiators and to direct all other unnecessary-for-cooling air and the turbulence created by the front tyre past the sidepods in order to minimise drag created by those.

Watching all other cars still using their barge boards and keeping in mind the little windtunnel testing Jaguar is able to do, I guess it's just some real time experimenting on a car wich suffers from major design problems.

[Red]

Every car uses barge boards for the reasons Dino mentioned (I thought that the most turbulences that may influence the air flow for the radiators are created by front suspensions, not wheels. Anyway, given the size and shape of a barge board I'm not sure how much turbulent air from the wheel they can deviate). But it is not necessary to place them as almost everybody does: in front of the radiators. I haven't notice Jaguar's but I'm sure that their barge boards are located IN front suspensions for the same effect, thus they may be smaller and not very visible. (just a thought: smaller = lighter car? OK, a couple of grams, but every gram saved counts...)

Williams were not the only team to use such a design. (Jordan and Benetton last year, if I am not mistaking). Even the sizes of the bargeboards are different from team to team: McLaren-huge, Ferrari-rather small.

PS: Is that a wing in front of the radiator? From this picture it looks like it generates lift, not downforce!?!?

[Dino IV]

Good observations, Red, you could be right here.
Didn't find another view but small barge boards inbetween suspension triangles seems allright, considering the high speeds at Hockenheim.

That black thingie in fromt of the monocoque could be mandatory to comply with some side-impact regulations.
It's indeed looking like it generates lift a bit, like this. Guess they can live with this small disadvantage as it probably will be benificial, directing more flow underneath the sidepods, into the diffusor.

The size of the barge boards is remarkable indeed.
Mac's large, Ferrari small and both varying per track.
Did you notice as well, that the Ferrari sidepod air intakes are almost 150% the size of the Macs? Really huge.
And still causing problems at high temperatures.
Those little Mac-chimney's must be pretty effective in their forced extraction.

[desmo]

The chimney-type extractors used on the MP4/15 and briefly seen on the Ferraris in practice at Magny-Cours appear to be designed to lift the exit above the turbulent boundary-layer air into the clean higher-velocity airflow up higher. This would use the difference in velocities to draw air out of the rad ducting courtesy of Bernoulli's principle.

They don't even exact the frontal area penalty you'd expect as in a front-on shot one can see that they are shrouded by the front wheels. They are also outboard of the rear wing, so do not shroud it's airflow. It looks pretty much like a free lunch to me.

The only potential downside I see is that if you optimise the ducting to take full advantage of the extractor effect and then find yourself behind a safety car on a hot day, the system might be somewhat velocity-sensitive relative to a conventional ducting arrangement. I speculated at the time that this may have been a factor in the apparent overheating experienced by the Macs in Adelaide.

Ferrari are testing a new version of this concept presently in preperation for Hungary. The chimneys they are testing are rather strange-looking, resembling bits off the Batmobile!

[Red]

Here:

I think that the bargeboard is visible in this picture. (looked for a top view, but couldn't find one). It would make more sense to me to use at Hockenheim large bargeboards (in order to reduce the drag, the engine is cooling OK at 350 km/h) and small in Monaco (to help cooling, drag is not that important as there are no long straights)

It appears that the role of the barge-boards is not critical, or not fully understood. Anyway, there is no a general consensus. If one of the teams had found a successful design(s), all would imitate it. Instead, almost every team on the grid uses it's own (more or less). For example, if my memory serves me right, Jaguar adopted the Mac's style at the beginning of the season and they dropped it by now. (it would be interesting to observe them at Hungaroring)

The air intakes at Ferrari are larger? Did not notice, as a matter of facts I was sure that F1-2000 has much smaller air intakes than F399 (their shapes looks like a "D", I mean that they are not rectangular anymore). There are some good pictures at F1-live (for example these: Ferrari but the all black silver arrows are not clear.

About chimneys. Deviating turbulent air from radiators above rear wheels thus reducing drag a little, or deviating hot air above tyres thus keeping them a little cooler? The last may allow the use of a softer compound. I think that is the main goal at Ferrari, as they already have problems with rear-tyre wear. Indeed they tested them prior Magny-Cours, but decided not to use them on high-speed circuits (drag). They will use them in Hungary (and they do look strange, not like chimneys but like a shark-fin. For the same problem I've heard that they are redesigning rear suspension geometry.

PS: The same black thingie! Well, not very clear from the picture, but I really hope that the bottom surface is parallel to the ground. Now, we do not want to see mr. Jonathan Bauer in action, again, for the same 3.12 Article in the Technical Regulations...