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They're always looking for more downforce, because to turn the cars, they need friction, which is a function of force pressing tire and tarmac together. OK. But there's another way to turn a car -- sideforce, directly from the aero. They can't do much of that by steering because they can't have any physical movable aero devices. But now they're into these "fluidic switches" for passive DRS and that's an extension of the F-duct concept, where one flow of air actuates or detaches another flow. So my idea is, can that be used in a legal sideforce steering system? There are 2 parts to this...

1. Since a circuit goes in one direction, there's more turning going on in that direction, and that tends to wear one tire more severely than the others, which causes a fall-off earlier. Maybe some of that wear can be moved to the other side, while also relieving the tires of having to do all the turning work. So rather than having all the car's aero force be downforce, make some of it sideforce, in favor of the predominant turning direction of the circuit of the week. If you let go of the wheel, the car will of itself want to turn in that direction. You keep it straight by holding the wheel against that sideforce, and over the course of the entire lap that aero-only turning force will be added to the turning force from tire traction boosted by downforce. It depends on the sideforce not coming completely at the expense of downforce; maybe there are areas of the car where they could generate sideforce without robbing it of any downforce.

2. Use the "fluidic switch" concept to deactivate or reduce the aero sideforce when the car's being turned in the opposite direction -- and, if possible, redirect some of that force into downforce instead. Then the car won't be working against itself so much, and it can be a gain overall -- less tire wear when turning in the aero-favored direction, and not much more wear on the straights or when turning in the opposite direction. And maybe not much more drag overall. The "switch" would not be activated by the steering system directly, but from the slight aero shear angle as the car's in the process of changing direction; maybe that could detach a flow and it would stay detached throughout the turn, then re-attach when the car turns back in the direction that the inherent sideforce favors.

The main point of the system is to increase overall turning performance over the course of the lap, while evening and reducing tire stress. There would need to be a different solution tailored to each unique track, so there are more gains than losses.

Also since aero sideforce does not depend on how hot the tires are, it could give an advantage in qualifying, the first lap, and out laps.

Well, it's just a rough idea, but what do you think? a possible gain overall? Pat? Adrian?

P.S. Maybe you could also use a DDRS that only ultra-stalls one side of the wing, or leaves one side stalled temporarily after the DRS closes, to help you rotate through Turn 1 at higher speed with less braking.

Shouldnt this be in the indepth motorsport forum??

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Mis-posted. Can't delete or move it myself now.

Post a new 1 there n ask mods to delete this...

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This sounds like it would work in lab conditions, however surely any gust of wind , or perhaps even dirty air would risk detaching the air flow at an unwanted time - could be dangerous?

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Good point, maybe they could leave it speed-activated like DDRS and have it only work in slower or faster corners, or else just leave it active all the time. Maybe that could still be a benefit by balancing the tire wear... because, i.e. on a clockwise circuit where the left-front takes a beating, you'd add rightward aero sideforce so the driver could use less steering input when turning right, and then he'd have to use more left steering when turning left to counteract the rightward aero sideforce, so maybe that would even out the wear and allow the entire set of tires to maintain performance for more laps -- enough to be worth a little extra drag. I mean if you lose a little top speed but have more even warm-up and can do one less pit stop, that seems like it might be worth it, maybe even for qualifying.

I'd pay money to know if they've tried this before, in wind tunnels or reality.

Eagerly waiting for Blinky McSquinty to reply.



This would be pretty hard, as the car would need to have a different braking setup for that turn alone. One side of the car would be planted, the other pretty much free. I dunno but the driver might just end up locking the hell out of the tires on the DDRS side.

They can't adjust brake bias left or right, but maybe the differential is allowed to help? Guess you're right, I'm just onto this idea that aero can be a direct turning aid somehow without breaching the regulations, and how this automatic flow-separation thing could be used along those lines. I'll even give it a name, "passive aerodynamic steering augmentation". KERS, DRS, DDRS, PASA... the more acronyms onboard the faster the car goes.

A passive fluidic switch that senses yaw could be designed. I guess the best place is in the nose, start with a hole in the nose. By directing airflow over a wing you could stall it, or augment lift, it all depends on the design. So you could have a front or rear wing that has more or less downforce on one side versus the other side, controlled by this fluidic switch.

You could also use vertical surfaces, such as the front wing mounts, turn vanes (what an appropriate name), and rear wing endplates, to just name a few, to generate a horizontal force. All of these could be controlled by the yaw sensing fluidic switch.

Cost versus reward. Such gimmicks would require a lot of resources to implement, and just how much would they increase performance?

Personally, I'd like to see gas turbines and use vectored nozzles as used in the Harrier. Instead of nozzles on the sides, just have two exiting, front and rear, on the top of the car. Point them backward to push forward, forward for braking, and sideways for cornering.


Throw in some afterburners and it would make a nice sight, especially in the night races.

But why? i mean you propose this solution to reduce tyre wear or heat in the tyre but that won't do that. Tyre will produce energy as long as a slip angle is achieved and the car cannot physically turn unless a slip angle is introduced (and vice versa) so while channeling air will cause the car to turn it will also result in a tyre slip angle which will result in energy and if it is to achieve the same result as turning the energy will be the same(and thus the heat).

What that could be useful for however is to limit driver hand movement by reducing steering input, and also could result in higher cornering speeds (similar to active suspension).

You know Nascar engineers are very clever in this, they use different suspension geometry on both sides such that the car wants to turn in the circuit direction (oval racing) and using aero to channel the car would be used by them if possible. However in F1 circuits turn both ways and thus suspension on both sides of the car is identical to make the car predictable and stable and using Aero in both directions can be used, but will add some degrees of complexity.


If such a system is to be implemented however as Blinky said above using Yaw sensers (gyros) to activate actuators which open vanes to channel the air can be used or even a driver can pre-select which "flap" to operate and when under braking the vane would open gradually (pre programmed) and that could assist in turning (similar to wing planes), this would make the car super light when turning and super quick as well, in chicanes the operation would be very critical and complex though.
The hardware is quite simple and already there in F1, the programming would be a bit complex.

The car can turn with negligible tire slip angle, if it's being yawed by something other than tire slip angle. If there's direct aero sideforce, that would be rotating you even if you had no wheels, then all you have to do is turn the wheels to the same angle (and the differential does its thing) and there's very little slip under the tires -- just a little because they are also rotating over the tarmac under the contact patches, it's not just the car rotating. But they'll take a lot less beating that way than if they were providing the force that's turning the car. Then if you want to turn more sharply you add in some tire slip angle to provide additional turning force, but you'll need less slip than if there were no direct aero helping. That's got to save some tire, when turning in the direction of the circuit. Then when you're turning in the opposite direction, if there's no fluidic switch cutting the aero sideforce then you'll need more tire slip angle to oppose the aero sideforce, and the net result will be transferring some of the wear and warm-up away from the side that was being over-worn and over-heated with a downforce-only car.


Think they could already do that by decreasing the pinion size in the steering rack. They'd probably have to do that too if using side-aero, because the driver will need to use more steering input when turning sharply against the track direction. Well, they could align the wheel so that straight is not really straight, but counteracting the aero at average speed.


Yeah I knew about NASCAR doing that, they have less aero to work with tho' and I don't think they have nearly as big or well-equipped and funded an aero department as an F1 team. In F1 they are going to spend ridiculous money on aero regardless, and maybe this sideforce thing despite its complexity would be a better place to spend it than getting another 1% out of the half-blown diffuser.


Wouldn't that make the driver's control a movable device capable of influencing the aero performance of the car?

Instead of detaching airflow to decrease down-force in a certain area, would it not be a better idea to for the car to generate 'side-force' as a car goes round the corner, or would the air pressure on the leading side of the car be too extreme to try to balance out on the outer low pressure side?

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I was thinking the other day if it would be legal to use the idea in the dyson airblade to create non-turbulent airflow over a wing... or would the "fan-car" regulation prevent also this?

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No i wouldn't say so, up to this point scientifically it is not yet known which is introduced first side force or slip (slip causes side turning force, or turning force causes slip). so both are in direct relation to each other and even if aero is rotating the car the car is still attached to the ground through the wheels so for it to turn, slip angle MUST be introduced and in value it wouldn't think it would differ to turning the car by steering since slip angle by definitions is the difference between where the wheels are pointing and where the car is actually going (and remember that you can't have side/Lateral force without slip angle). If you are driving casually on the highway in a less stable car and lets say a truck speeds by you the side force may cause your light car to move sideways, on the tyres this has the same effect as you turning your car and slip angle will be introduced.

Slip angle also introduce heat and that is why i claim whether turning the car by aero or not the tyres will generate the same heat and lose the same energy.

About my proposal with the flaps you are right that would introduce an aero movable device similar to DRS, but other methods could be made too like the Fduct (also illegal )

That's what my main idea is, not messing with the downforce, but using direct aero force to help turn the car, and if possible modulate that with the fluid switch concept.

I think it would add some instability around the yaw axis, but that's exactly how they make fighter aircraft more maneuverable (except the instability is in pitch, I think, so they can turn more aggressively in a bank). Basically the plane wants to rotate, so you have to work to hold it straight but when you do want to turn the plane does that better because it's what it naturally wants to do.I'm not suggesting that level of instability, but if there is sideforce coming and going without direct control then it's going to buffet the car a bit -- if they use a fluidic switch to modulate it.

Alternatively, it might be useful just as steady force to one side, and then I don't think it would destabilize the car -- just make it naturally pull in the direction of the circuit.

It might not need to be a LOT of force, just enough to help reduce tire wear and, of course, help the car take key corners faster. It might actually slow it down in some corners, so they'd have to plan it so it helps through longer corners. They do this already, trading off downforce vs. straight-line speed, so it would be just another element to plan.



Just having a friendly discussion, but if I were the Green Goblin, flew alongside Grosjean and physically pushed the front of his car away from Alonso, and he turned the wheels to face along the same arc I'm turning him on, then how is there slip angle? The tires are aimed in line with the tarmac that's passing underneath them, exerting no side-force.

Whether or not we're going to call it "slip angle", at that point the tires are not experiencing as much degradation as they would if they were doing the work of turning the car. It's the other force -- be it Goblin or aero -- that's doing the work, hence saving at least one of the tires.

Total Turning Force = Tire Turning Force + Aero Turning Force.

So if we're adding an aero component to the force that's turning us through a corner, then we need less force from the tire.

Tire Turning Force = Shear Force on the Tire Compound

It seems like since we'd need less tire turning force, there would be less shearing force on the tire compound, and therefore it would not be "worked" as much and should last longer.

If that's wrong, what have I missed?

I think you are confusing turning force with tyre slip angle. the turning force is something concerning the whole vehicle and is a force reacting on the tyres. Slip angle is the result/cause of that force.

To continue on your green goblin example, the car is aiming straight and then you push its front end sideways. the tyre remains straight then how is it turning? the tyres are still touching the ground, so if teh car is turning the wheels must now be moving sideways without actually turning. you can make it turn but by no more that the tyre allows without change of direction (i.e maximum slip angle before the tyres lose traction) which let's say for F1 cars is about 3.5 degrees and then tyres start losing grip and sliding all over.(G forces will decline)

By the simple definition: Slip angle is the difference between where the wheels are aiming and where the car is heading.



Now you say the driver aims the tyres to the exact direction they are turning on by your Green Goblin force but initially the tyres are experiencing a side force (caused by your power) and have produced a slip angle, turning in will not really solve that, as the driver now will need to maintain that same slip angle or else the side force will change, so he cannot aim the tyres to where the car is heading.



Slip angle vs lateral force is a tyre characteristic, can't have one without the other. tyre technology haven't passed that yet.

EDIT: about your post there are some things i would like to highlight:

Total Turning Force = Tire Turning Force only, as long as they are the only thing in contact with the ground

Tire Turning Force = caused by a tyre slip angle, or causes the slip angle.

convinced?

I'd have said the difference between the rotational plane of the wheel, and the direction tarmac is passing under the contact patch -- that's not exactly the same as the car's heading, there's toe-in and camber to consider, and when the car has oversteer or understeer, the tarmac is approaching from a direction other than where the car is aimed.

In my example, the tire does not remain straight, the Goblin starts the push smoothly and the driver instantly keeps the wheels aimed along the path the car is following over the ground, at all times. I call that zero slip angle as it relates to turning. and yet the car is turning, because the lateral force is not coming from the tires but something else.

When I drive through a cross-wind, I have to steer against it. That means the total turning force is the sum of the tire turning force and whatever other turning force there is, be it wind, Goblin, collision, or aero bodywork. The force of the Goblin's push can't be discounted just because the wheels are on the ground. What if it's a slippery surface?


Nope, sorry Guess we'll have to build and test it.

You are right with your definition as the plane, but it is still the difference between the wheel plane and the actual car path., Toe is an induced static slip angle it is not a directional problem, camber doesn't really affect direction (on a 4 wheel car) and i think saying it is the wheel plane we solved that bit.

You see your second and third paragraphs counter each other and support my claim.

Third paragraph:
When in a cross wind, the side force caused by the wind causes lateral movement of the car, which in turn induces a slip angle which you have to steer against to neutralize and keep the car straight. there is no turning force in that instant, the turning force is cause by you to counter act the wind force. the tyre sees both. if you assisted the wind then the tyre will see a total of 2 forces and produce a slip angle according to the sum of that.

2nd paragraph
The lateral force may not be caused from the tyres but they certainly are reacted from there, every single force created by the car is reacted upon by the tyre that is simple physics as they are the only support for the car and they do all the work.

To turn the car by 2Gs using aero, the tyres will have to induce/react a force=ma (a=2G in that instant) so each tyre will have to react to its supported mass (counting weight transfer) x 2G.

no to the paragraph itself, now that we have established from the third paragraph that the wind caused the tyres to induce a slip angle and thus you steered to react that, the same effect will be made from the aero/Goblin. If you aim the tyres to the theoretical path you are heading to you will get understeer as this way you didnot account for the slip angle caused. there is no such thing as a force produced that is not reacted upon by the tyres. the engine drives the car but the tyres react to its torque (and induce a slip angle as well!)
If you have induced a force a slip angle will be created (look at the graph in my post), it is impossible for this not to happen.


the graph shows that when cornering at 1G the tyre will produce around 9 degrees of slip angle which the driver will overshoot the path with. doesn't matter how the force is created, it is reacted upon by the tyres. the only case this is not true at is if the car is spinning while being held up and tyres are not touching anything.


Trust me in the tyre bit i am entirely confident on it, i have worked on tyre modelling for a bit now. Prove me wrong and i will owe you an apology

I am not shooting down your concept, don't misunderstand me, as i said it can be used to make the cars quicker in the corners but it won't be saving energy.



P.S on a slippery surface the same concepts still apply only that the tyre now has new characteristics when in contact with the new surface (lower force holding capabilities and force vs slip curves more steep)

Anyway I'm not sure where all this ends up but am still convinced that if something else is helping turn the car, the tires must be spared some stress and degradation, however it ends up working technically.

hahahahaha yeah Wi-Fi is good!, yes i used data from a testing machine too to model tyres and vehicle dynamics models for my schools Formula student team. and i am now working on another similar project.

I guess we will have someone else separate us on that bit then

This discussion seems to be about two separate forces (vectors) generating side force required to negotiate a corner. Each is distinct and quite separate from the other. One theory is the use of aerodynamic pressure to generate such force, and the other is what the tires do to additionally contribute to this turning force.

In every form of motorsport I can think of, the tires are relied upon to generate such force. It is theoretically possible to use aero to vector sideways, but instead it is used to generate downforce, and thus assist the tires in doing their job. If you deploy some aerodynamic device to vector sideways, it will degrade downforce, and the tires will not contribute as much to the total effort, yet work just as hard. Every component in a Formula One car is a series of compromises, and I'm 100% sure that if you generate sideways vectors through deployment of an aerodynamic device, the loss of downforce will result in a net loss of cornering ability.

Formula One is a competition, and everything is used and stressed to 100% of it's life and ability. If you do not work your tires as hard as the competition, you probably won't make the grid because you are too slow. And it's the same with aero, the wings are on the verge of stalling out, DRS also follows that same path, the top teams have their wings balanced in the razor's edge of stalling out.

If you take that to using aero to generate sideways vectors, because of the basic nature of competition, they will run at the very edge of stability, and I would not like to be a driver negotiating 130R when a crosswind shows up. And to be honest, although an interesting subject, it is presently illegal for such a device to be used. And if you attempt to maintain stability (as in the case of the F-16 with it's computers constantly adjusting the controls just to keep the aircraft from losing control) only the driver is allowed to control the car.

Isn't the end result similar to Mclaren second brake pedal back in the day which got banned after someone took a picture of inside the cockpit.

does anyone know what rule it was banned under?

4-wheel steering


I haven't been talking about any kind of driver or electronic-controlled aero, nor any movable elements, btw.

There's a major aerodynamic problem with the aerodynamic yaw that I don't think anyone has brought up yet. In aircraft there are 3 primary control surfaces and each control has 3 effects, primary effect of ailerons is to roll the aircraft around the longitudinal axis, primary effect of elevators is to pitch the aircraft on the lateral axis and the primary effect of the rudder is to yaw the aircraft about the vertical axis. These 3 everyone knows. But the secondary effects of these flight controls are still that powerful that you can fly a plane perfectly safe with only two of three flight controls operating. It's not pretty but it works.

As we are talking about yawing the car around a corner the rudders secondary effect comes into play massively. Secondary effect of the rudder is roll, in an aircraft if you apply left rudder only the first thing you will notice is you feel out of balance and then roll left... Not yaw, but roll. As the rudder applies a yawing motion the wing on the outside is effectively traveling faster than the inside. Therefore more lift on the outside. Therefore roll as the wing is a far more powerful aerodynamic device than the rudder.

Formula 1 car is basically the same only the wings are producing lift in the opposite direction, therefore yaw left, roll RIGHT. Applying more force to the outer wheel and cancelling out if not overpowering the force you are trying to avoid. Bottom line it would have at best no effect and more likely a detrimental effect on tyre life as well as making the car aerodynamically unstable. Bad juju

Damn I love aerodynamics

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"Applying more force to the outer wheel and cancelling out if not overpowering the force you are trying to avoid"

could you elaborate farther on that?

And either way, roll won't be a problem in F1 caqrs as their roll stiffness is very high (something like 0.01 degrees per G or even less), i think you mean that weight transfer would also increase which is true.

But my point is that i don't think that is possible with the current tyres.

Sounds so clever to me! Rear wheel steering on road cars (built into the suspension) has been proved to help traction, tracking and tyre wear.
Flyer, you should be working for Mercedes! They need help at the rear. Very interesting idea.

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"And either way, roll won't be a problem in F1 caqrs as their roll stiffness is very high (something like 0.01 degrees per G or even less), i think you mean that weight transfer would also increase which is true."

The roll stiffness may be high but I think that basically if you tried to turn the car using aerodynamic forces to reduce the forces on the front outside tyres you will basically just be swapping one force for another. A yaw produced from aerodynamic forces of the car might allow you to turn slightly tighter at the same when deflection or use less tyre deflection for the same corner but the load on the tyres will not change. I think you might be able to reduce the slip angle or tyre shear but the extra force applied by the wing over that tyre pushing down would cancel it out.

There could be another draw back too in that for a yawing motion it would have to have an axis to rotate around. Probably not too big an issue if the axis is at the rear axle but if its forward of the axle then a portion of the force pushing the front tyres in will be pushing the rear tyres OUT. So save the fronts at cost of the rears? Probably not a great compromise.

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Yes i agree with most you are saying. No matter where the force is from, the tyres will have to react it, if it can't there is no force and the tyres will lose traction.

As for saving the tyres there is no alternative than less loading on them, and thus less speed. the better team will be the team using all 4 tyres more than the competition as Blinky said.

Even if they steer the car only with the tires, the "one side of the wing traveling faster than the other" effect applies whenever they are going around a curve, not just if they're steering with aero elements.

I think the only difference (other than tire stress increase/decrease, setting aside that debate for the moment) is that if aero is pushing the car left, that's pushing air right somewhere, which can have an effect on the rest of the aero. Maybe it could even help... if they have a clever arrangement.

There could be worse rolling moment from the aero "rudder" but only if it were below the center of gravity while the car's turning the same way it's pushing. If it were above the CG, then it would counteract the rolling moment from the imbalanced wing while turning in the direction of the circuit, and help prevent that inside front tire from locking up as that's usually the first to go.

You may have produced an issue here. In a left turn, air by one car is channeled to the right. that would make it extremely difficult to a car on the outside to overtake it as it is being pushed to an understeery situation

Looks like they already use at least part of the idea

I think this is closer to what Nascar do than you suggested idea. and i really don't think they do that as F1 tacks are a mix of right and left corners so doing different geometries will cause the car to be different pending on the corner direction. I would be blown away if they manage to do this