Increasing Down force through Rotation of wheels

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ss.vamsikrishna
ss.vamsikrishna
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Joined: 24 Nov 2005, 14:02
Location: USA

Increasing Down force through Rotation of wheels

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It may sound weird but i think it is possible , f1 wheels has a huge rpm so in the wheels say there are vanes like propeller which can suck large volume of air at high speed and force it to under of the car , cant we increase the downforce , by Bernoulli's Theorem as velocity of air getting sucked will be so high that pressure will be very low and it will create a huge down force . i cannot reckon exactly ......... so is it possible.
FIA has regulations on this also....
any ideas please let me know........... :?:

manchild
manchild
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Joined: 03 Jun 2005, 10:54

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Propeller/fan shaped wheel spokes are prohibited by FIA.

ss.vamsikrishna
ss.vamsikrishna
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Joined: 24 Nov 2005, 14:02
Location: USA

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ok suppose it was allowed , will it enhance any aerodynamic downfore
see no add ons just rpm of wheels and vanes........

RH1300S
RH1300S
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Joined: 06 Jun 2005, 15:29

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I suppose it must be possible, but it's hard to visualise exactly how.

I'm sure you can devise the wheels to act as pumps, but they will need to extract air from very specific locations. Also, even if they are good pumps - they would need to be pumping into an area of lower pressure (I think) around the wheels otherwise they won't be pumping much at all.

With an open underbody, it's hard to see how this can work. Perhaps with a full skirted underboy and nose dam it might work. But then I'm sure a solution like the Gordon Murray's fan car would do the job better.

manchild
manchild
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Joined: 03 Jun 2005, 10:54

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Perhaps it could work if air is sucked sideways, pass trough wheel and than exit trough some chimney upwards.

DaveKillens
DaveKillens
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Joined: 20 Jan 2005, 04:02

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If there were wheel spokes designed to draw air in from the chassis side, and exhaust it away from the car, I don't see much advantage, apart from excellent brake cooling.
The negative aspects add up. First, it take energy to move that much air, stolen directly off the wheels. Top end would drop.
Secondly, with that much air being forced sideways, if each corner of the car wasn't perfectly equal to it's counterpart, there would be a disastrous tendency for the car to want to go sideways, probably at the worst instance. Third, so much dirty air would be thrown up, the chances for passing would diminish. And presently, with this new split wing, they want better overtaking possibilities. Fourth, and most important, spectator safety. With twenty cars going by the same spot for approximately seventy laps, eventually the side-blowing air would send a pebble, or some object into a fan, most likely resulting in injury. You ever stand beside one of those large grass cutters and see how violently objects are thrown to the side?
So, IMO, blowing air throught the wheels and directly sideways isn't feasible.
Even if some form of chimney was built, one that could survive and work, venting the air straight up looks like a bad proposition too. First off, they would add unsprung weight.... booo. Secondly, in case of damage or rupturing, the venting of air through the defect would probably force the car to want to go sideways at speed.
Talk to any aerodynamicist, and one of the most valid and important parameters is drag versus downforce. The goal is to get maximum downforce for minimum drag.
If you attach vanes to the wheels, they will definitely require a lot of power from the wheel. That would rob the drivetrain of power. And yes, by directing the air straight up would result in downforce, it would come at a huge price of drag (in the form of lost power at the wheels). Terribly inefficient, that way. And the interesting part is that the spokes would demand the most power at the higher speeds. Top speed would definitely drop.
So in the end, we have the suction car, but this time with the suction driven off the wheels. That would make for a wide car.

manchild
manchild
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Joined: 03 Jun 2005, 10:54

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Something that came to me as I was thinking about fan shaped wheels but without concern for downforce generating.

Imagine wheel spokes shaped as fan with variable geometry.

Neutral positions on straights (as common spokes)…

Example for right turn:
In right turn spokes on wheels on right side of the car get into position to suck in the air from right side while spokes on the left side get into position to blow the air to left. That way the fan spokes would propel the car in direction opposite of G-force in turns.

Same thing in left turns with opposite procedure.

No gain in downforce but possible partial G-force counter effect. In another words – fighting against the same enemy downforce fights with but in different way.

:idea: :?:

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Sawtooth-spike
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Joined: 28 Jan 2005, 15:33
Location: Cambridge

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Surely the air would be better used cooling the brakes? if you rammed the air into the intakes using the wheels and rims that would improve performace (as long as u held them at optimum heat).
also if there was some aero stuff done with the tires and rims, then the air flow that would be created would effect air going into the brake air intakes.

RH1300S
RH1300S
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Joined: 06 Jun 2005, 15:29

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manchild wrote:Something that came to me as I was thinking about fan shaped wheels but without concern for downforce generating.

Imagine wheel spokes shaped as fan with variable geometry.

Neutral positions on straights (as common spokes)…

Example for right turn:
In right turn spokes on wheels on right side of the car get into position to suck in the air from right side while spokes on the left side get into position to blow the air to left. That way the fan spokes would propel the car in direction opposite of G-force in turns.

Same thing in left turns with opposite procedure.

No gain in downforce but possible partial G-force counter effect. In another words – fighting against the same enemy downforce fights with but in different way.

:idea: :?:
Wow.....that's what I call lateral thinking (no pun intended BTW :D)!!!

I'd hate to try an ally this to your idea about in-wheel suspension ;) - my mind can't cope with all of that at once.

It could be difficult on a road car...imagine sucking small dogs into the wheels on one side and if it's wet hosing people with water of the other side..... 8) :twisted:

manchild
manchild
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Joined: 03 Jun 2005, 10:54

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RH1300S wrote:It could be difficult on a road car...imagine sucking small dogs into the wheels on one side and if it's wet hosing people with water of the other side..... 8) :twisted:
I was thinking about F1 (if it was allowed). Small dogs...? Well there could be a grill fitted on the outer side - too small for Chihuahua or cat but big enough for rat :lol: deratization on the road :lol:

Seriously, I wonder how much thrust could fan-spoke wheel generate spinning at high speeds?

wowf1
wowf1
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Joined: 05 Jan 2004, 13:53
Location: Brunel University, England

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dang manchild you beat me to the post with that idea! I had that idea while learning about variable turbine vanes about a year ago. ie. using the thrust generated by variable-vane wheels to increase the available centrepetal force. I even went as far to try and calculate the generated thrust manchild, but to no avail because I tried to factor in the drag of the air hitting the side of the F1 car's body work and this made things quite complicated (being only a Level 1 undergraduate, I had to do all the leg-work myself!) But having said that, I'm convinced that the effect is significant, and would love to see it in action! Imagine the possible cornering speeds!

The only thing I would be concerned about (although I'm sure F1 teams would figure it out) is balancing the thrust provided by the front & rear wheels, and deciding what end of the car needs more thrust.

Another use that's just sprung to me is would it be possible to use the vanes to control oversteer? I know the vanes could rotate fast enough, but could they create a fast enough pressure difference to stop the oversteer?

I don't know, but it's food for thought hey!

rob

manchild
manchild
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Joined: 03 Jun 2005, 10:54

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Sorry :wink:

To me it is obvious that it could work as sort of traction/stability control if it the system could react quickly. Blowing shouldn’t be the problem below the nose, especially on keel-less cars with slightly streamlined bottom of the front end of the cockpit but rear end would bring more headache. Perhaps something like brake ducts only positioned according to overall aerodynamic could be the solution for all 4 wheels (blowing the air straight up?).


Imagine it on dusty Australian Rally :wink: …sideways at 100 mph … or in Sepang, no fancy covered stands would protect the public from rain
:lol:

ss.vamsikrishna
ss.vamsikrishna
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Joined: 24 Nov 2005, 14:02
Location: USA

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if CFD analysis is done using this concept , we can understand the air flow
beneath the car in much better way. say the front tyres suck in the air
and are diverted to flow beneath the car and the rear tyres suck the air
outside from beneath the car there will be amazing air flow beneath the car
not only as u guys said it can be used from engine cooling , to brakes cooling to steering aid and this huge high speed air can be used to pump in to engine sth like turbo charger does and it will increase the air quantity in the cylinders and
producing much more powerful power strokes and in addition to that it
will produce amazing ground effect through bernoulli principle.

i think this is a very good research topic :D

DaveKillens
DaveKillens
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Joined: 20 Jan 2005, 04:02

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One of the current high tech ducted fans in existence is a 50 inch diameter fan that generates 20,000 pounds of thrust. Of course, it's optimized for efficient airflow, but if you take that into account, and do some rough calculations, a Formula One wheel could generate as much as three, maybe four thousand pounds of thrust. That of course would require a lot of power too, which wouldn't matter too much since they would be used in braking/cornering scenarios, where power isn't as critical.
So we're not talking chicken feed here, this is brute force on a large scale. If such a system was built, the entire vehicle would have to be designed around the airflow requirements. So I wouldn't worry about strakes or keels, they would be redundant in such a system. Those wheels/ducted fans would be moving a LOT of air.
As fas as building a wheel that not only carries the mechanical loads, yet is also a variable pitch ducted fan, I don't see any obstacles.

But we are talking about variable geometry aero devices, which are definitely banned from Formula One. IMO, if you have variable geometry aero, why not have huge (and I mean HUGE) wings that adjust according to requirements. And why not throw in vertical fins, which could also be programmed to generate a lot of side force.

RH1300S
RH1300S
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Joined: 06 Jun 2005, 15:29

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ss.vamsikrishna wrote:if CFD analysis is done using this concept , we can understand the air flow
beneath the car in much better way. say the front tyres suck in the air
and are diverted to flow beneath the car and the rear tyres suck the air
outside from beneath the car there will be amazing air flow beneath the car
not only as u guys said it can be used from engine cooling , to brakes cooling to steering aid and this huge high speed air can be used to pump in to engine sth like turbo charger does and it will increase the air quantity in the cylinders and
producing much more powerful power strokes and in addition to that it
will produce amazing ground effect through bernoulli principle.

i think this is a very good research topic :D
I like this thread, started off with a strange question...but has drifted somewhere fun..........

I don't think you need to pump air under the car at the front - just as long as it's being removed fast enough at the other end it goes in for free; so why use energy pumping it in.

I wonder how much energy it would take to rotate "pump wheel" at high speeds? Obviously to get any pumping effect it the energy has to come from somewhere - in this case it's the engine. So, there is a horsepower penalty in using the wheels as a pump.

How about on an oval? If the thing was blowing to the outside of a turn, could the drive ride a cushion all the way around?

BTW - I cannot see that any of this would give a net performance advantage (you MIGHt gain on the swings, but you would lose on the roundabouts ;)); but it's a fascinating idea that's been bought up.