Re: Far more important than banning TC

WebSlave wrote:
Phil Newnham wrote:

Bigger cars -> bigger hole in the air -> easier to get a draft.

I believe this is not so true anymore, because with smaller engines a
lot of the air is going through between the back tyres and the
bodywork. They should block that airflow by changing the rules to
create the "bigger hole in the air". With all cars about the same
width, they only need a "hole" as big as the car - whatever width it
may be. Just changing the maximum/minimum total width wouldn't help
much.

You misunderstand what the wake of an F1 car looks like. The air that now goes around the engine cover does not fill in the hole, it feeds the rear wing, which then creates a huge upwash of air, most of which goes over the car behind completely. The flow you're talking about will never get near the front of the car behind.

http://www.fia.com/resources/images/1306371943__CDG_Air_Flow_graphic.jpg

If you look at the top plot (if you want to have a discussion about why I intensely dislike the CDG plot, let me know, but within the limitations of CFD, the top plot is acceptable) you can see how the flow you're talking about is in green where it comes through the rear wing and is swept up by the wake from the diffuser, which appears as the sharp blue/green interface. It's the diffuser flow along with the vortices that form at the widthwise edges of this flow that cause the problem. What you can't see on the figure is the huge draggy wakes off the rear wheels, which do act more like you suggest, and do create a low pressure zone that extends backwards in line with the ground, except that they will also interact with the vortices and become entrained in the general wake. Any action that makes the car's wake smaller will improve the pressure recovery inside the wake, making the low pressure region smaller.

Also, wider track -> more mechanical grip -> less aero dependency
-> easier to follow the guy in front through corners.

This is not a logical chain like the one above, as a wider track
doesn't produce more mechanical grip. New, wider tracks increase
overtaking, but that's an independent factor.

Wider track increases mechanical grip by reducing weight transfer, AIUI.

They've abandoned the idea of radical aero restrictions, as well. All
they really need to do is ban diffusers.

Or affect the airflow by changing the bodywork rules. I haven't read
about abandoning the planned aero restrictions, but then again, I
haven't read anything about them at all for a while.

It was in the same article that I linked to in my OP.

The best/only way to solve that is to increase mechanical grip
and reduce aero, and yet the FIA are consistently moving in the opposite
direction.

We agree on the principle. But FIA hasn't in any way helped to
increase the aero grip either. The latest major aero rule changes
(lifting the front wing and moving the back wing forward) both reduced
aero grip.

Only marginally, and the increased airflow you mentioned due to the reduction in engine size has made the rear wing more effective by supplying it with better flow quality at the same time as the FIA are trying to make it worse. The front wing changes are clawed back by ever more complex end plate designs and wing trailing edge treatments, rewarding those who spend the most money, as with every change. The most useful thing they could do to reduce the effectiveness of the wings would be to limit the chord, and if they increased the aspect ratio at the same time and made the cars wider, they would increase the low pressure region behind the car.

--
Phil

http://www.usefilm.com/photographer/31307.html
.

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