Mercedes F1 W05 Pre-launch Speculation

[spiritone]

It wasn't just an aero advantage that made them better than merc, it was the phenomenal traction out of slower corners that gave them a big edge over everyone. How they accomplished that is still a mystery but whatever they had it also helped tire wear. Less slippage, less tire wear. Combine the two equals killer car. The big question is, that tech applicable to this years car?

[Anon123]

It wasn't just an aero advantage that made them better than merc, it was the phenomenal traction out of slower corners that gave them a big edge over everyone. How they accomplished that is still a mystery but whatever they had it also helped tire wear. Less slippage, less tire wear. Combine the two equals killer car. The big question is, that tech applicable to this years car?

I think the general consensus was that Red Bull's traction came from a DF advantage and clever engine mapping.

[spiritone]

Df doesn't stop the wheels from spinning, clever engine mapping, i'm sure thats part of it Somehow i think they have something more clever than that.

[Anon123]

Df doesn't stop the wheels from spinning, clever engine mapping, i'm sure thats part of it Somehow i think they have something more clever than that.

DF actually does... It's much harder for a wheel to spin when it's being pressed into the ground. Obviously DF isn't as effective at low speed but it still has an affect on wheel spin.

[beelsebob]

Df doesn't stop the wheels from spinning, clever engine mapping, i'm sure thats part of it Somehow i think they have something more clever than that.

Uhhh, yes, yes it does. Df means that more force is applied to the rubber onto the tarmac, which means that there's more friction, which means that the tyres spin less.

[godlameroso]

An F1 car needs to be going about 120kph or more for downforce to begin creating an effect, and about 160-170 before it starts influencing traction. In Singapore there are a lot of corners where you're going less than 120kph and yet Red Bull was still getting on the power earlier.

[trinidefender]

An F1 car needs to be going about 120kph or more for downforce to begin creating an effect, and about 160-170 before it starts influencing traction. In Singapore there are a lot of corners where you're going less than 120kph and yet Red Bull was still getting on the power earlier.

You are looking at this the wrong way. Downforce has a fairly linear increase when you compare it to an increase in velocity. That is just the downforce created by the wings.

When you add in the very good sealing effect of the floor and diffuser that they were able to achieve, it allows them to run more rake in the car and produce more downforce at low speeds. How these diffusers are designed with the flip up between the floor and the diffuser creates a situation where at very high speeds part of the diffuser actually stall. The rear end of the car squatting down from the downforce created at high speeds somewhat reduces the rake at the rear of the car and essentially smoothness out the pressure gradient. This goes some way toward keeping the diffuser working at high speed but all the same at some point the diffuser designed like these are will stall.

Now the downforce created with the exhaust and vortex sealed floor is actually going to be rising at a less than linear rate when compared to velocity before dropping off some point when the diffuser starts to stall.

Next you can add in that not all of the exhaust gasses will be on the floor. Some will be acting on the wing like rear brake ducts increasing downforce. However as you speed up the downforce produced by these brake ducts will be less and less affected by the exhaust and more and more affected by the airflow coming around the car. This means that again you have a less than linear downforce vs speed situation.

The net result of all this is that downforce at low speed is probably going to be higher (proportionally to the speed that the car is moving) than downforce at high speed. Finally closing off I am sure it is safe to say that yes, even in the low speed corners, downforce is quite important.

[humble sabot]

...
The net result of all this is that downforce at low speed is probably going to be higher (proportionally to the speed that the cat is moving) than downforce at high speed. Finally closing off I am sure it is safe to say that yes, even in the low speed corners, downforce is quite important.

Well more accurately, getting the exhaust effects and pitch effects to work perfectly in concert would give a lowspeed downforce advantage to that team. Hell maybe Vettel just found a trick with the throttle that helped him do a little manual blowing!

[Lycoming]

An F1 car needs to be going about 120kph or more for downforce to begin creating an effect, and about 160-170 before it starts influencing traction. In Singapore there are a lot of corners where you're going less than 120kph and yet Red Bull was still getting on the power earlier.

You are looking at this the wrong way. Downforce has a fairly linear increase when you compare it to an increase in velocity. That is just the downforce created by the wings.

Downforce and drag generally increase proportional to the square of velocity.

Furthermore, simple calculations with rough assumptions will show that downforce is not negligible even at 90 km/h.

[godlameroso]

I don't disagree, downforce is being produced even as low as 40kph, but is it's effect enough to influence traction? If you notice the onboards the drivers rarely floor it before 160kph, below that they're dancing with the throttle. It's true however, if you can make more low speed downforce then you can use more throttle sooner, and this gave you even more downforce in 2013. In 2014 the production of downforce will be far more linear, albeit not completely as trini pointed out.

The fact that downforce production isn't completely linear goes to show how important tuning a conglomerate of systems and effects works towards the overall goal, and it's an impressive feat of engineering to say the least.

[turbof1]

An F1 car needs to be going about 120kph or more for downforce to begin creating an effect, and about 160-170 before it starts influencing traction. In Singapore there are a lot of corners where you're going less than 120kph and yet Red Bull was still getting on the power earlier.

That's easy: downforce created by the coanda exhaust isn't dependent on car speed. Same goes for clever engine maps. Red bull supposedly had the best tech on that front.

[trinidefender]

An F1 car needs to be going about 120kph or more for downforce to begin creating an effect, and about 160-170 before it starts influencing traction. In Singapore there are a lot of corners where you're going less than 120kph and yet Red Bull was still getting on the power earlier.

That's easy: downforce created by the coanda exhaust isn't dependent on car speed. Same goes for clever engine maps. Red bull supposedly had the best tech on that front.

To some degree this is true. As in the downforce created directly on the brake ducts. However other than that all the exhaust is doing is sealing the diffuser. This isn't directly creating more downforce is it. It is just allowing them to:
1. Run the car with more rake.
2. Design the diffuser differently.
3. Some combination of the two.

If they were feeding the high speed exhaust gasses into the diffuser then yes that woul be directly creating downforce with the exhaust. Like what MLaren tried to do with the mp4-26 fan tail (octopus) exhaust.

If somehow I have missed something and you can see how they can directly create downforce with the exhaust then let me know.

[shelly]

I think it is unlikely that exhust have a big effect on aero on rear brake ducts, except maybe some ntrainment and downwash from the better working diffuser.

[SiLo]

I Suppose if you can somehow direct the exhaust flow into the flow from the diffuser you might be able to accelerate it slightly, but I doubt it would have much of an effect.

[spiritone]

Next year with the changes to the exhaust will RBR still have the same traction? I'm betting they will.Whether it was mapping or some even more clever trick they found something that had nothing to do with aero. We probably will be talking about this again.