Keels (the difference)

[coysht]

Keels

For future reference, this thread explains the difference between the different types of lower front suspension mounts.


Single Keel

The lower wishbones are connected to a 'keel' which protrudes out of the bottom of the nose section of the chassis. Lower wishbones can be made as a single piece.

This is the old standard layout for the second half of the 1990's. Allowed the lower areas of the chassis to be raised for improved airflow under the car.


Twin Keel

The lower wishbones are mounted to separate keels which protrude from the lower corners of the chassis.

Developed to further improve airflow under the nose of the car.
Small side keels are prone to flexing.


V-Keel

Lower wishbones mount to an upside-down ‘A’ frame instead of a single keel.

Designed to allow airflow through the keel itself. Should be nearly as stiff as a single keel and with a partial improvement in air flow.


‘Zero’ Keel

Lower wishbones mount to the bottom corners of the chassis. In effect using stunted twin keels.
Both upper and lower wishbones are angled upwards to the chassis to allow this layout.

Has same aerodynamic benefits as twin keel, but is significantly stiffer.
Does lead to a compromised suspension geometry and reduced roll-stiffness.


‘Interchangeable’ Keel
no shown on diagram

Invented by a member of thescuderia.net (Tobes) in early 2006 to explain all the rumours about the keels that years Ferrari was supposed to have, this is basically a hybrid of all other types of keel that would in theory allow you to change from one to another by un-bolting various parts of the chassis, in the area behind the nosebox.
Unfortunately (for Tobes, as it meant he was talking rubbish) it was not used on the '06 Ferrari and is unlikely to ever be used due to the inherent structural weaknesses of not having your suspension mounts bonded into the chassis.

[quasi celestial]

Can I just add that the upper wishbones of the zero keel also aid the airflow coming off the front wing. It apparently has quite a benefit particularly since the new (05) front wing regs were introduced.

[coysht]

Originally posted by quasi celestial
Can I just add that the upper wishbones of the zero keel also aid the airflow coming off the front wing. It apparently has quite a benefit particularly since the new (05) front wing regs were introduced.

I don't know if there is a specific benifit to the zero keel upper wishbones that helps aid air flow.

McLaren's may well have done, but if you look at the BAR, they have a totally different profile to the upper wishbones.

You should be able to achieve the same thing by profileing the wishbones of a single keel suspension layout. I think its more wishbone specific than keel specific.

[Tifoso]

Nice work Tom

[Angelus]

Wooh now i know keel differences

[Jack Newtown]

Excellent work Coysht! Hats off to you.

As far as I understand though wishbones are not aerodynamic components as stated so in the rule book. Of course their profile is designed to create as little drag as possible as well as provide adequate room for the trackrods housed within. Of course teams may be tickling the dragon with the FIA but this probably seems unlikely as these components are within view. Not nearly as clever as hiding a second fuel tank to get your car a few kilos under regs. ;)

[coysht]

Originally posted by Jack Newtown
Excellent work Coysht! Hats off to you.

As far as I understand though wishbones are not aerodynamic components as stated so in the rule book. Of course their profile is designed to create as little drag as possible as well as provide adequate room for the trackrods housed within. Of course teams may be tickling the dragon with the FIA but this probably seems unlikely as these components are within view. Not nearly as clever as hiding a second fuel tank to get your car a few kilos under regs. ;)

The wishbones themselves cannot be aerodynamically profiled (the have zero chamber in aero speak) but I believe they can be given a slight angle of attack which will generate either an upwash or downwash behind it (depending on preference).

Also, I believe you can profile the joint to the chassis to managed the airflow as you want (see McLaren MP4-21 below)



Finally if you position the wishbones in the correct place and set the front wing right, you can get the air coming off the top edge of the front wing flap to pass between the upper and lower wishbones.

TBH this really isn't bending the rules much if at all. Things like flexing rear wings and stuff are much more dodgy.


The BAR car didn't technically have a hidden fuel tank. All cars have a collector in them, it's just that BAR counted the fuel within it as part of the car.

[coysht]

From another thread in the main forum:

Originally posted by SS454
coysht, you sure the MP4-17D was a duel keel? I thought the 18 was their first go at it. And if the 17D did have a duel keel, did the 2002 mp4-17 chassis also carry this keel design?

Yes I am sure it was twin keel.

The 17D was not actually a new monocoque, but the ones used in the previous half of the 2002 season updated. So both had the same layout of suspension mounting.

The left keel and suspension of the MP4-17D that won at Sepang 2003.

[Tommy_F]

Wow! Cool stuff. THX everybody

[coysht]

The Red Bull BR2 V-Keel:

[quasi celestial]

I've read a lot of times that the V-keel has the same aero benefit of the no-keel but I've also read that the no-keel works so well because it removes not only the central bulb from critical airflow but also the lower wishbone. Infact I read in Autosport that Honda were pushed down the no-keel path because the lower front wishbone had given them a lot of gip on the 007. If this is the case the V-keel can't have the same aero benefit because as we can see the LF wishbone is in the same position as single keel. I think this is also backed up by the fact that so many more teams went no-keel than V-keel.

If V-keel had the same aero benefit and none of the structural shortfalls of the no-keel then it seems logical everyone would've gone down this path. So I think it's fair to speculate that, relative to each other, the V-keel has a structural advantage whereas the no-keel has an aerodynamic advantage.

[coysht]

Originally posted by quasi celestial
I've read a lot of times that the V-keel has the same aero benefit of the no-keel but I've also read that the no-keel works so well because it removes not only the central bulb from critical airflow but also the lower wishbone. Infact I read in Autosport that Honda were pushed down the no-keel path because the lower front wishbone had given them a lot of gip on the 007. If this is the case the V-keel can't have the same aero benefit because as we can see the LF wishbone is in the same position as single keel. I think this is also backed up by the fact that so many more teams went no-keel than V-keel.

If V-keel had the same aero benefit and none of the structural shortfalls of the no-keel then it seems logical everyone would've gone down this path. So I think it's fair to speculate that, relative to each other, the V-keel has a structural advantage whereas the no-keel has an aerodynamic advantage.

The V-keel is alegedly part way between a single and zero-keel layout in terms of aerodynamics (although there have been rumours that its much closer to the single keel than Renault will have us believe). Yet maintains most if not all of the geometry and stiffness of a single keel.

The Zero keel layout is much more extreme in how it clears the path for air under the nose, normally involving raising the underside of the nose of the monocoque (unless your BMW Sauber) and so the air flow is alot better (if your car is optimised for this), but the geometry is not as good, and (I believe) the roll stiffness is reduced.

[quasi celestial]

Good we agree :)

It seems a lot of publications are convinced the V-keel has the same aero benefit as No-keel...

[coysht]

Originally posted by quasi celestial
Good we agree :)

It seems a lot of publications are convinced the V-keel has the same aero benefit as No-keel...

Unfortunately alot of the technical publications get things wrong quite often, if they can't be sure about something, they will often print their guesses as fact - which is a shame.

[fermy]

With V-keel v no-keel the tradeoff is obvious. But what about V-keel v single keel?

Logically, it seems to me that V-keel should have some advantages over the single keel and no disadvantages. However some teams, notably Ferrari, still use single keel, so that logic must be flawed, which brings forward the natural question. What are the advantages that a single keel has over a V-keel?

[coysht]

Originally posted by fermy
With V-keel v no-keel the tradeoff is obvious. But what about V-keel v single keel?

Logically, it seems to me that V-keel should have some advantages over the single keel and no disadvantages. However some teams, notably Ferrari, still use single keel, so that logic must be flawed, which brings forward the natural question. What are the advantages that a single keel has over a V-keel?

The V-keel is likely to be everso slightly more flexable than the single keel.

Also, to make the most of the small hole in the V of the keel, I would guess you need to change the nose and front wing to channel the air towards it.
I can see that if you didnt modify the airflow towards the keel, you could actually loose more than you gain due to there now being two obstructions, as opposed to one (even if they are thinner).

If your front wing has been optimised for the design of the rest of your car you could end up re-designing the entire car to make the most of the keel, and its unlikely that you would want to change everything just for a small improvement in air-flow under the nose.


A Zero keel is easier to see the benifits with, and possibly requires less nose/wing modifications, and for any changes you do make, the pay back should be more significant.

[jkwaggener]

These threads really just keel me!

[antares]

Originally posted by coysht
The V-keel is likely to be everso slightly more flexable than the single keel.

Also, to make the most of the small hole in the V of the keel, I would guess you need to change the nose and front wing to channel the air towards it.
I can see that if you didnt modify the airflow towards the keel, you could actually loose more than you gain due to there now being two obstructions, as opposed to one (even if they are thinner).

If your front wing has been optimised for the design of the rest of your car you could end up re-designing the entire car to make the most of the keel, and its unlikely that you would want to change everything just for a small improvement in air-flow under the nose.


A Zero keel is easier to see the benifits with, and possibly requires less nose/wing modifications, and for any changes you do make, the pay back should be more significant.

I wouldn't bet on that. I'd in fact hazard a guess that the V keel could be stiffer than no keel, for the same amount (and more critically, weight) of material you use.

Also, with the zero-keel, the payback in aerodynamic terms would most certainly be more significant... but your suspension no longer does much, and you're effectively using your tyres as shocks to get that extra aero gain.

[coysht]

Originally posted by antares
I wouldn't bet on that. I'd in fact hazard a guess that the V keel could be stiffer than no keel, for the same amount (and more critically, weight) of material you use.

I thought that was implied by what I said - sorry if I gave the impression that it was otherwise.

Originally posted by antares
Also, with the zero-keel, the payback in aerodynamic terms would most certainly be more significant... but your suspension no longer does much, and you're effectively using your tyres as shocks to get that extra aero gain.

I did mention that the aero gain of the zero keel should be more significant.
However I think saying that the "suspension doesn't do much" is a little extreme - your suspension geometry is compromised away from the optimum but this can be compensated for elsewhere - it still does what it used to, just with reduced roll-stiffness (as you dont have a direct link between the two wheel uprights)

[BrotherWolf]

I must say a big thanks. I never realised that there were different kinds of keel and that the different F1 teams use different keels.

[coysht]

The main post of this thread has been updated to include a 5th design of keel....

And for referance here is a list of who used which design of keel in 2006:

Renault - V
McLaren - Zero
Ferrari - Single
Toyota - Zero
Williams - Zero
BAR - Zero
Red Bull - V
BMW Sauber - Zero
Midland - Zero
Toro Rosso - Single
Super Aguri - Twin (and huge keels at that)


Watch this space for a 2007 update (yeah, I know its not THAT interesting but it keeps some of us amused)

[Tifoso]

It is hugely interesting mate (really) Thanks!


EDIT: your sigbar: woooooooohaaaaaaahaaaaaaaa

[coysht]

Originally posted by Tifoso
It is hugely interesting mate (really) Thanks!

I'm just getting myself worked up for the most interesting part of the season (for me anyway) when all the new cars come out - with any luck this technical forum may get some decent use for a change.

Originally posted by Tifoso
EDIT: your sigbar: woooooooohaaaaaaahaaaaaaaa

Was wondering how long it would take before someone noticed that!

[Tobes]

‘Interchangeable’ Keel
no shown on diagram

Invented by a member of thescuderia.net (Tobes) in early 2006 to explain all the rumours about the keels that years Ferrari was supposed to have, this is basically a hybrid of all other types of keel that would in theory allow you to change from one to another by un-bolting various parts of the chassis, in the area behind the nosebox.
Unfortunately (for Tobes, as it meant he was talking rubbish) it was not used on the '06 Ferrari and is unlikely to ever be used due to the inherent structural weaknesses of not having your suspension mounts bonded into the chassis.

Brilliant.....


Good job on the explanations....

[coysht]

Brilliant.....


Good job on the explanations....

You mean it's taken this long for anyone to notice that little addition!?!

[pilotHans]

The main post of this thread has been updated to include a 5th design of keel....

And for referance here is a list of who used which design of keel in 2006:

Renault - V
McLaren - Zero
Ferrari - Single
Toyota - Zero
Williams - Zero
BAR - Zero
Red Bull - V
BMW Sauber - Zero
Midland - Zero
Toro Rosso - Single
Super Aguri - Twin (and huge keels at that)


Watch this space for a 2007 update (yeah, I know its not THAT interesting but it keeps some of us amused)

any information on 2007 list

ferrari are using single or V keel's for this season? hmmm

[coysht]

2007 Cars (In car number order)

McLaren - Zero
Renault - V
Ferrari - Zero
Honda - Zero
BMW Sauber - Zero
Toyota - Zero
Red Bull - Zero
Williams - Zero
Toro Rosso - Zero (well its the Red Bull car anyway)
Spyker - Zero
Super Aguri - Zero (assuming that they do try and run last years Honda)

[durden]

These threads really just keel me!

Iowans...

[zakfourie]

How do you know all this stuf??
It's very very interesting!!

[coysht]

Red Bull - Zero
Toro Rosso - Zero

Or maybe not... The Red Bull twins have actually got small keels sticking out of the chassis to mount the lower wishbones as opposed to bolting them straight into the chassis.

So that'd technically make them Twin Keel.