Mercedes W13

[marcel171281]

Mercedes did a brilliant job with rule examination to introduce this element. If they manage to redesign their sidepods for 2023, to widen them, keep them sloped rearwards and keep the wing, they might have a good chance to generate more downforce than Ferrari and Red Bull can.

I can very much imagine that a lot of other teams will come up with this downwash element in 2023. I keep thinking about the 2017 Ferrari sidepod/impactstructure solution, which was a similar clever solution in that erea. In 2018 everyone (apart from the winning Mercedes) had it.

[SiLo]

downwash will vary at different speeds.

Eh, no. It doesn't. Downwash is affected only by lift coefficient and wing planform geometry, so basically - wing geometry. Without this downwash, the car would have even less downforce. I'm sure the drag/downforce trade-off was well worth it, it usually is with these downwashing elements, they can really make a difference.

Mercedes did a brilliant job with rule examination to introduce this element. If they manage to redesign their sidepods for 2023, to widen them, keep them sloped rearwards and keep the wing, they might have a good chance to generate more downforce than Ferrari and Red Bull can.

Are the radius restrictions on the sidepods? Is it possible they could run something like the Ferrari/Alpine but even more extreme?

[matteosc]

downwash will vary at different speeds.

Eh, no. It doesn't. Downwash is affected only by lift coefficient and wing planform geometry, so basically - wing geometry. Without this downwash, the car would have even less downforce. I'm sure the drag/downforce trade-off was well worth it, it usually is with these downwashing elements, they can really make a difference.

Mercedes did a brilliant job with rule examination to introduce this element. If they manage to redesign their sidepods for 2023, to widen them, keep them sloped rearwards and keep the wing, they might have a good chance to generate more downforce than Ferrari and Red Bull can.

Are the radius restrictions on the sidepods? Is it possible they could run something like the Ferrari/Alpine but even more extreme?

There are restrictions in terms of geometry. For example the sidepodes that Mercedes currently has are "thicker" at the base, which is something you do not usually want (you would rather go with an undercut). This is because of the "rearview mirror stay" element, which counts as a sidepode section. KYLENEGINEERING did an interesting YouTube video explaining this.

I do not think this design is necessarily the winning one, even when fully developed, years down the road.

[ringo]

downwash will vary at different speeds.

Eh, no. It doesn't. Downwash is affected only by lift coefficient and wing planform geometry, so basically - wing geometry. Without this downwash, the car would have even less downforce. I'm sure the drag/downforce trade-off was well worth it, it usually is with these downwashing elements, they can really make a difference.

Mercedes did a brilliant job with rule examination to introduce this element. If they manage to redesign their sidepods for 2023, to widen them, keep them sloped rearwards and keep the wing, they might have a good chance to generate more downforce than Ferrari and Red Bull can.

Change the speed of the car in your simulation and see for yourself.
Go from low speed and share that image.
And go to high speed and share that image of the streamlines.

Have you seen the cars drive in the rain?
The rooster tails behind the rear wings are basically downwash, Just in the opposite orientation.
What happens when they drive faster?

[ringo]

Mercedes did a brilliant job with rule examination to introduce this element. If they manage to redesign their sidepods for 2023, to widen them, keep them sloped rearwards and keep the wing, they might have a good chance to generate more downforce than Ferrari and Red Bull can.

I can very much imagine that a lot of other teams will come up with this downwash element in 2023. I keep thinking about the 2017 Ferrari sidepod/impactstructure solution, which was a similar clever solution in that erea. In 2018 everyone (apart from the winning Mercedes) had it.

They wont be able to have it working properly with wide sidepods. The wing or blade, will be too close to the surface of the sidepod itself.
Remember Ferrari were the first ones to introduce these sidepod wings years ago.
The effect will not be the same between the two concepts. The mercedes are able to exploit it because the wing is in free air without any nearby surfaces.

[matteosc]

Mercedes did a brilliant job with rule examination to introduce this element. If they manage to redesign their sidepods for 2023, to widen them, keep them sloped rearwards and keep the wing, they might have a good chance to generate more downforce than Ferrari and Red Bull can.

I can very much imagine that a lot of other teams will come up with this downwash element in 2023. I keep thinking about the 2017 Ferrari sidepod/impactstructure solution, which was a similar clever solution in that erea. In 2018 everyone (apart from the winning Mercedes) had it.

They wont be able to have it working properly with wide sidepods. The wing or blade, will be too close to the surface of the sidepod itself.
Remember Ferrari were the first ones to introduce these sidepod wings years ago.
The effect will not be the same between the two concepts. The mercedes are able to exploit it because the wing is in free air without any nearby surfaces.

You cannot just add the downwash element, it would be against regulation (see my previous post).
Also, I am not sure why would other team want to copy the Mercedes solution. RedBull and Ferrari's concept seems to be working well...

[Vanja #66]

Are the radius restrictions on the sidepods? Is it possible they could run something like the Ferrari/Alpine but even more extreme?

From my understanding of the rules, they could play on the edge of the rules and keep the best of both worlds. But, now every team knows how they did it so everyone would be able to examine this solution and implement it. Rear part of the sidepods needs to be wide, that much is clear. Ferrari somehow manage things on the knife edge there, but only because of cable-stay concession from the pre-season.

Merc can have a tiny inward angle of sidepod sidewall in the rear (RB has slightly outward or completely straight, but it's not a big difference) and would need to keep elongated inlets. This part is not ideal, but maybe it can be negated in some other way.

Change the speed of the car in your simulation and see for yourself.
Go from low speed and share that image.
And go to high speed and share that image of the streamlines.

Have you seen the cars drive in the rain?
The rooster tails behind the rear wings are basically downwash, Just in the opposite orientation.
What happens when they drive faster?

Let's try another way... We know front wing upwash affects the entire car. We know this is very important for flow management and overall pressure distribution. We know teams take great care of this and haven't had problems with this for decades already.

On the other hand, we know teams do 99% of CFD simulations at 50 m/s for a full size car. We know they directly compare this to a 60% scale wind tunnel model at the same speed. With similarity theory applied to aerodynamics, this scale difference is equivalent to the same speed difference if both models were full scale.

This means full scale car going 50m/s is directly comparable to full scale car going 30m/s. (Teams don't seem to care about what happens at higher speed also, wonder why...) So, no, upwash and downwash don't change in practice for the speed range of an F1 car. If there would have been any pracitcal use of aerodynamics bellow 30 m/s (108 km/h) then there might have been a problem with fixed geometry of an F1 car.

The biggest impact on up/downwash is lift coefficient for the same planform geometry. In theory, this changes slightly for a wing of same geometry at very low Reynolds number, i.e. very low air velocity. In practice, you don't care much what happens when car is going that slow.

To respectfully answer the rest of the plethora of questions - yes, I've seen race cars running in the rain. Live and on TV. Have you taken a good look at this phenomena when a car is accelerating on a straight? Do remember that water drops are heavy and affected by gravity compared to air. Maybe take a good look again and answer your own question.

[ringo]

You are writing too much.
I simply asked you to verify if the downwash will change with speed.
Teams don't run wind tunnel at one speed. The run it at various speeds.

A lot of circumlocution in your post.
If there was no difference aeordynamically at such a wide range of speeds, teams would not need to test their cars at low, medium and high speed. They would not be able to predict what happens when DRS opens, how the suspension behaves at full downforce vs low etc.
So I think you should go back to the drawing board on some of the claims you made. It could confuse readers.

You know very well the torsional moments on the wing will increase with speed, an indication of the resultant forces on the wing, and as well the downforce and thus downwash.

velocity is a component here:

[AR3-GP]

You are writing too much.
I simply asked you to verify if the downwash will change with speed.
Teams don't run wind tunnel at one speed. The run it at various speeds.

A lot of circumlocution in your post.
If there was no difference aeordynamically at such a wide range of speeds, teams would not need to test their cars at low, medium and high speed. They would not be able to predict what happens when DRS opens, how the suspension behaves at full downforce vs low etc.
So I think you should go back to the drawing board on some of the claims you made. It could confuse readers.

You know very well the torsional moments on the wing will increase with speed, an indication of the resultant forces on the wing, and as well the downforce and thus downwash.

F1 teams only test at 1 speed which is rougly 50m/s which is the maximum tunnel speed permitted by the FIA and quite frankly way too slow for what teams want anyway so they always operate at the maximum. The fact that DRS can be deployed above that speed doesn't matter. "Torsional moments" don't matter because the deflection of windtunnel parts has no correlation to full scale. The windtunnel model is made of entirely different materials to full scale.

[ringo]

You are beating around the bush.

Testing is done at varying speeds. And the aerodynamic behavior changes with speed.

I love this kinds of discussions, because it will force the bold claims to be demonstrated.

[ringo]

You are writing too much.
I simply asked you to verify if the downwash will change with speed.
Teams don't run wind tunnel at one speed. The run it at various speeds.

A lot of circumlocution in your post.
If there was no difference aeordynamically at such a wide range of speeds, teams would not need to test their cars at low, medium and high speed. They would not be able to predict what happens when DRS opens, how the suspension behaves at full downforce vs low etc.
So I think you should go back to the drawing board on some of the claims you made. It could confuse readers.

You know very well the torsional moments on the wing will increase with speed, an indication of the resultant forces on the wing, and as well the downforce and thus downwash.

F1 teams only test at 1 speed which is rougly 50m/s which is the maximum tunnel speed permitted by the FIA and quite frankly way too slow for what teams want anyway so they always operate at the maximum. The fact that DRS can be deployed above that speed doesn't matter. "Torsional moments" don't matter because the deflection of windtunnel parts has no correlation to full scale. The windtunnel model is made of entirely different materials to full scale.

So you are saying they test at only 1 speed?
So why dont the FIA say you shall test ONLY at 50m/s

[dialtone]

You are writing too much.
I simply asked you to verify if the downwash will change with speed.
Teams don't run wind tunnel at one speed. The run it at various speeds.

A lot of circumlocution in your post.
If there was no difference aeordynamically at such a wide range of speeds, teams would not need to test their cars at low, medium and high speed. They would not be able to predict what happens when DRS opens, how the suspension behaves at full downforce vs low etc.
So I think you should go back to the drawing board on some of the claims you made. It could confuse readers.

You know very well the torsional moments on the wing will increase with speed, an indication of the resultant forces on the wing, and as well the downforce and thus downwash.

F1 teams only test at 1 speed which is rougly 50m/s which is the maximum tunnel speed permitted by the FIA and quite frankly way too slow for what teams want anyway so they always operate at the maximum. The fact that DRS can be deployed above that speed doesn't matter. "Torsional moments" don't matter because the deflection of windtunnel parts has no correlation to full scale. The windtunnel model is made of entirely different materials to full scale.

So you are saying they test at only 1 speed?
So why dont the FIA say you shall test ONLY at 50m/s

Don't know if they test with 1 or 2 or 100 speeds but the answer to this is quite obvious: not everyone has a 60% scale wind tunnel, so mandating a given high speed would mean some teams can't use theirs. So they just mandate a maximum speed.

[AR3-GP]

You are writing too much.
I simply asked you to verify if the downwash will change with speed.
Teams don't run wind tunnel at one speed. The run it at various speeds.

A lot of circumlocution in your post.
If there was no difference aeordynamically at such a wide range of speeds, teams would not need to test their cars at low, medium and high speed. They would not be able to predict what happens when DRS opens, how the suspension behaves at full downforce vs low etc.
So I think you should go back to the drawing board on some of the claims you made. It could confuse readers.

You know very well the torsional moments on the wing will increase with speed, an indication of the resultant forces on the wing, and as well the downforce and thus downwash.

F1 teams only test at 1 speed which is rougly 50m/s which is the maximum tunnel speed permitted by the FIA and quite frankly way too slow for what teams want anyway so they always operate at the maximum. The fact that DRS can be deployed above that speed doesn't matter. "Torsional moments" don't matter because the deflection of windtunnel parts has no correlation to full scale. The windtunnel model is made of entirely different materials to full scale.

So you are saying they test at only 1 speed?
So why dont the FIA say you shall test ONLY at 50m/s

This discussion probably doesn't belong here anymore, but the bulk of the testing is carried out at 50m/s. It's getting a bit pedantic now. If you try and do speed sweeps for every single model part change, you won't get anything done in your time allotment. The downforce above and below 50m/s is extrapolated from simple mathematical formulations where the non-dimensional lift and drag coefficients are scaled by some factor of the velocity. That's how Mercedes can match a downforce and drag number to their simulator at every speed, even though the tunnel has only generated the aero map at 50m/s. There are set times when they will pause the development program and do the granular ride and speed sweeps (for example, the launch spec car configuration, or an "upgrade package" will have a granular wind tunnel mapping for correlation with the full size car), but it's not on every single wind tunnel run. It cost too much time.

[ringo]

But you are singing a different tune. Anyhow.
But to get back on topic. That wing on the crash structure will exhibit different behavior along the range of speeds that the car drives.

I did a CFD investigation years ago on this site of the blown front exhuast of the lotus car. Those images are probably lost now. But exhaust shielding the underfloor exhibited varying behavior at the speed. Likewise with coanda exhuasts and blown diffusers.

In the same way that we see front wing elements deflect as speed increases due to increase loading, the downwash on those wings by the sidepods will developed varied strength of vortices and downwash.

All I am saying this varied behavior can contribute to Merc having a car that operates in a small window.

I am yet to see evidence to support otherwise. It would be nice if the CFD capable guys could run the studies and share the results for low, medium, and high speed, and transient.

[uchihaigor1701]

So if what you say is true. So probably this w13 is a test subject for an eventual w14?