Mercedes W13

[Just_a_fan]

Don't be embarrassed, wishful thinking gets to the best of us all sometimes.

Found it!

Is it just the camera angle though?

https://i1.wp.com/cdn-1.motorsport.com/ ... ns-and.jpg

Same design adjusted differently

Same design, different viewing angle for each wing.

[chrisc90]

According to Greek motorsport journalist Dimitris Bizas, the Milton Keynes-based team has engineered a new rear suspension that can adapt to conditions after hitting 250 kmph and cuts out the bouncing caused by porpoising.

The w13 isnt made in milton keynes

The guy in video says RB.

[AA_2019]

So the basic solution is:

1) to use a low downforce rear wings,
2) use front floor vanes to create powerful vortices to seal the floor edge
3) develop suspension with some form of switch like function to control the bouncing at higher speeds

Probably a lot harder than it sounds

[Just_a_fan]

3) develop suspension with some form of switch like function to control the bouncing at higher speeds

Would that not be contrary to the new rules on what the suspension may do?

[AR3-GP]

3) develop suspension with some form of switch like function to control the bouncing at higher speeds

Would that not be contrary to the new rules on what the suspension may do?

Teams can design their suspension to do whatever they like, within the bounds the regulations. If they can engineer a switching function within a very prescriptive ruleset, then that's just being more clever.

[Stu]

3) develop suspension with some form of switch like function to control the bouncing at higher speeds

Would that not be contrary to the new rules on what the suspension may do?

Teams can design their suspension to do whatever they like, within the bounds the regulations. If they can engineer a switching function within a very prescriptive ruleset, then that's just being more clever.

Suspension must be mono tonic in operation
https://encrypted-tbn0.gstatic.com/imag ... -Y4_jJ6Q&s

[AR3-GP]

Would that not be contrary to the new rules on what the suspension may do?

Teams can design their suspension to do whatever they like, within the bounds the regulations. If they can engineer a switching function within a very prescriptive ruleset, then that's just being more clever.

Suspension must be mono tonic in operation
https://encrypted-tbn0.gstatic.com/imag ... -Y4_jJ6Q&s

Monotonic does not mean linear. It only means constantly increasing rh, or constantly decreasing rh.

So a team can implement a system where the spring rates increase sharply at a kinematic switch point. That might be how one could reduce porpoising at high speed without compromising tire wear and low speed grip.

[matteosc]

Teams can design their suspension to do whatever they like, within the bounds the regulations. If they can engineer a switching function within a very prescriptive ruleset, then that's just being more clever.

Suspension must be mono tonic in operation
https://encrypted-tbn0.gstatic.com/imag ... -Y4_jJ6Q&s

Monotonic does not mean linear. It only means constantly increasing rh, or constantly decreasing rh.

So a team can implement a system where the spring rates increase sharply at a kinematic switch point. That might be how one could reduce porpoising at high speed without compromising tire wear and low speed grip.

Agree, but there is also some constraints in terms of the suspension characteristics, which needs to be fixed and not "time dependent". I think this constraints makes it difficult to design a suspension that "simply" behaves differently at different speeds.

[AR3-GP]

Suspension must be mono tonic in operation
https://encrypted-tbn0.gstatic.com/imag ... -Y4_jJ6Q&s

Monotonic does not mean linear. It only means constantly increasing rh, or constantly decreasing rh.

So a team can implement a system where the spring rates increase sharply at a kinematic switch point. That might be how one could reduce porpoising at high speed without compromising tire wear and low speed grip.

Agree, but there is also some constraints in terms of the suspension characteristics, which needs to be fixed and not "time dependent". I think this constraints makes it difficult to design a suspension that "simply" behaves differently at different speeds.

Here's what I think. Such a system isn't behaving differently because of speed. It's behaving differently because of ride height. There is a correlation between speed, downforce, and ride height. That's why a team can predict that the suspension "changes" at X km/h. Because at X km/h, you generate Y Newtons of downforce, and Z mm of angular displacement of the rocker.

My guess is the geometry of the rocker causes a non-linear motion ratio. The non-linear motion ratio is what causes the effective heave stiffness to change after a certain displacement of the rocker.

Will probably get yelled at for going off topic so that's all I add.

I guess the W13 would benefit from proper implementation of such a system. They seemed to have such a system last season causing the opposite effect. The heave stiffness would drop above a certain speed.

[matteosc]

Monotonic does not mean linear. It only means constantly increasing rh, or constantly decreasing rh.

So a team can implement a system where the spring rates increase sharply at a kinematic switch point. That might be how one could reduce porpoising at high speed without compromising tire wear and low speed grip.

Agree, but there is also some constraints in terms of the suspension characteristics, which needs to be fixed and not "time dependent". I think this constraints makes it difficult to design a suspension that "simply" behaves differently at different speeds.

It's not behaving differently at different speeds. It's behaving differently at different rideheights. There is a correlation between speed, downforce, and rideheight. In this is the answer and it's something the W12 utilized last season to great effect. The W13 likely still has this feature, but is entirely useless due to porpoising meaning there is no ride height control.

Yes, I agree with what you are saying, but you are just describing a stiffening suspension. The issue is that, for example, when you hit kerbs, even at low speed, you have a big suspension excursion, most likely higher than what you have when hitting 250 km/h on the straight. If you set your suspension to have a very stiffening characteristics you can run into trouble when hitting bumps or kerbs, especially considering that anti-roll bar typically only add stiffness on roll motions (hitting kerbs) to the non-roll motions (downforce effect on straights).

There must be a balance somewhere, but obviously it is not that trivial to find, or Mercedes would have found it already.

[AR3-GP]

Agree, but there is also some constraints in terms of the suspension characteristics, which needs to be fixed and not "time dependent". I think this constraints makes it difficult to design a suspension that "simply" behaves differently at different speeds.

It's not behaving differently at different speeds. It's behaving differently at different rideheights. There is a correlation between speed, downforce, and rideheight. In this is the answer and it's something the W12 utilized last season to great effect. The W13 likely still has this feature, but is entirely useless due to porpoising meaning there is no ride height control.

Yes, I agree with what you are saying, but you are just describing a stiffening suspension. The issue is that, for example, when you hit kerbs, even at low speed, you have a big suspension excursion, most likely higher than what you have when hitting 250 km/h on the straight. If you set your suspension to have a very stiffening characteristics you can run into trouble when hitting bumps or kerbs, especially considering that anti-roll bar typically only add stiffness on roll motions (hitting kerbs) to the non-roll motions (downforce effect on straights).

There must be a balance somewhere, but obviously it is not that trivial to find, or Mercedes would have found it already.

I think this video will help. It more or less explains what teams can do for the non-linear heave stiffness. Third spring only activates below a certain rideheight because of geometry of the suspension and rockers.

[matteosc]

It's not behaving differently at different speeds. It's behaving differently at different rideheights. There is a correlation between speed, downforce, and rideheight. In this is the answer and it's something the W12 utilized last season to great effect. The W13 likely still has this feature, but is entirely useless due to porpoising meaning there is no ride height control.

Yes, I agree with what you are saying, but you are just describing a stiffening suspension. The issue is that, for example, when you hit kerbs, even at low speed, you have a big suspension excursion, most likely higher than what you have when hitting 250 km/h on the straight. If you set your suspension to have a very stiffening characteristics you can run into trouble when hitting bumps or kerbs, especially considering that anti-roll bar typically only add stiffness on roll motions (hitting kerbs) to the non-roll motions (downforce effect on straights).

There must be a balance somewhere, but obviously it is not that trivial to find, or Mercedes would have found it already.

In a well designed modern F1 suspension, the corner stiffness, and heave stiffness. are independent. That's why we talk about a "third spring" on formula cars for heave stiffness. Random suspension excursions on one side of the car coming from a curb or a "pothole" are only controlled by the corner stiffness. Uniform pitch/heave motions of both wheels are only controlled by the heave stiffness mechanism.

I agree with you in principle, but I don't think they are completely uncoupled, as we always see teams struggling to find the right balance on suspension stiffness.

My point is that if it was that easy, they would not have porpoising problems after 2-3 races.

[AR3-GP]

Yes, I agree with what you are saying, but you are just describing a stiffening suspension. The issue is that, for example, when you hit kerbs, even at low speed, you have a big suspension excursion, most likely higher than what you have when hitting 250 km/h on the straight. If you set your suspension to have a very stiffening characteristics you can run into trouble when hitting bumps or kerbs, especially considering that anti-roll bar typically only add stiffness on roll motions (hitting kerbs) to the non-roll motions (downforce effect on straights).

There must be a balance somewhere, but obviously it is not that trivial to find, or Mercedes would have found it already.

In a well designed modern F1 suspension, the corner stiffness, and heave stiffness. are independent. That's why we talk about a "third spring" on formula cars for heave stiffness. Random suspension excursions on one side of the car coming from a curb or a "pothole" are only controlled by the corner stiffness. Uniform pitch/heave motions of both wheels are only controlled by the heave stiffness mechanism.

I agree with you in principle, but I don't think they are completely uncoupled, as we always see teams struggling to find the right balance on suspension stiffness.

My point is that if it was that easy, they would not have porpoising problems after 2-3 races.

Nothing in F1 is easy Some teams just make hard problems look easy.

[Lefty8]

It doesn't work that way.
A lower drag rear wing does not evacuate the diffusor as effectlively so throat velocity will be lower = less downforce.
it may solve the choking/stall in the floor but downforce will be lost. At best it will make the car more drivable and that may help the driver extract more lap time at the expense of tyre wear. But they may be able to race better and minimise points loss while they solve the problems with the car

No matter how much the floor is helped by rear and beam wings, getting it closer to the ground is several times more beneficial for downforce. Just look at RB18 at Saudi Arabia, "tiny" rear wing and floor scraping the ground all the time...

yes f course because they will be changing the geometry of the tunnels by doing so. So what they're doing with a low ownforce rear wing is really just a band aid they hope will give them more speed but that is also not necessarily going to work because a higher ride height means slower air flow under the car and that creates drag too.

[AA_2019]

Remember this from the Pre season test…

https://www.gpblog.com/en/amp/105344/fi ... elona.html

The jigsaw puzzle is starting to come together. Whatever innovation Red Bull have to effectively switch the suspension at higher speeds, Merc need to copy it.