Lotus E20 Renault

[scarbs]

that's just a rotary damper, Brawn won a WDC with them

[corner1flatout]

that's just a rotary damper, Brawn won a WDC with them

interesting what you said about their front layout.
perhaps their use is dependent on the circuit - high speed, low speed, rear-limiting vs front-limiting.

concerning the rear, have you given any thought to the E20 having no torsion bars.
just 2 rotaries, and the "third" damper.

renault have always seemed to have a mechanical grip advantage throughout the years.

[scarbs]

that's just a rotary damper, Brawn won a WDC with them

concerning the rear, have you given any thought to the E20 having no torsion bars.
just 2 rotaries, and the "third" damper.

I don't believe Lotus (Renault) use\d Rotaries. Although teams have not run torsion bars in the past, the need for non linear heave stiffness, means that teams that they are more commonly used nowadays. Often reacting against each other, via a tie bar to remove their spring rate affecting the roll stiffness.
My understanding is that they do use torsions bars, as well as a heave spring\damper, an anti roll bar and a roll damper. This allows the team to elect not to run side dampers (linear not rotary types) for certain set ups. This set up as well as linking the torsions against each other, rrather against the chassis means side, heave and roll springing and damping are totally decoupled.
Then of course is their innovation from a few years back when they linked the front and rear heave dampers to prevent pitching under braking

[corner1flatout]

I don't believe Lotus (Renault) use\d Rotaries. Although teams have not run torsion bars in the past, the need for non linear heave stiffness, means that teams that they are more commonly used nowadays. Often reacting against each other, via a tie bar to remove their spring rate affecting the roll stiffness.
My understanding is that they do use torsions bars, as well as a heave spring\damper, an anti roll bar and a roll damper. This allows the team to elect not to run side dampers (linear not rotary types) for certain set ups. This set up as well as linking the torsions against each other, rrather against the chassis means side, heave and roll springing and damping are totally decoupled.
Then of course is their innovation from a few years back when they linked the front and rear heave dampers to prevent pitching under braking

immensely informative! thanks as always.

decoupling... the holy grail!

can you do a post on your site,
of what typically a top team's program is from friday till the end of saturday?
which things do they concentrate on more than others
and give the most "bang for their buck" towards optimizing lap times?

[thisisatest]

My understanding is that they do use torsions bars, as well as a heave spring\damper, an anti roll bar and a roll damper.

what i dont get is if they have a heave spring (for, duh, heave) and an anti roll bar, why have the torsion bars at all? or leave off the anti roll bar and go with only torsion and heave. one part is definitely redundant, and i find it hard to believe it's there only for adjustment convenience, considering the packaging space that could be saved and extra ballast, c of g, etc...

[scarbs]

You need torsion bars because the heave spring doesn’t engage until the suspension has compressed a certain amount, so the torsion bars support the static load (i.e. weight of the car) and the heave spring then supports the dynamic load (weight and aero load)

[FlYiNgIcEmAn]

Craig Scarborough ‏@ScarbsF1
Pat Symonds in @F1racing_mag suggests the rules banning Mercs DDRS (i.e. DRS operated) may not apply to the passive Lotus system

[turbof1]

"may not apply" so I assume any doubt about the legality of Lotus' passive system in 2013 would be about any further TDs/rule changes, which would be next aside the DDRS ban.

[Huntresa]

Well we still dont know if it has anything to do with the DRS, i mean the pylon is just located there so it can move air to that area not work in conjuction with the DRS, it just happens to be a coincidence that they are both in the same place.

[PlatinumZealot]

It is a blown wing that adds downforce - at least when DRS is off.

[hardingfv32]

It is a blown wing that adds downforce

Please expand... Roughly how do you blow the bottom of the wing to gain downforce?

Brian

[PlatinumZealot]

Blow a high speed jet of air under the wing to increase the overall velocity under the wing. In the Lotus E20 VD thread i will make a post showing some CFD results. the first test I did, where the slots point backwards, there is a 13% to 20% increase in downforce, but an increase in drag of 6%. I will post a more refined result before Spa weekend.

[amouzouris]

Blow a high speed jet of air under the wing to increase the overall velocity under the wing. In the Lotus E20 VD thread i will make a post showing some CFD results. the first test I did, where the slots point backwards, there is a 13% to 20% increase in downforce, but an increase in drag of 6%. I will post a more refined result before Spa weekend.

but does the air have enough velocity after it travels through the tubing to produce more downforce?

[MarkedOne8]

Shall we see pelican nosecone in low-downforce circuits like Spa and Monza?Is it universal upgrade, or just for high downforce circuits?

[turbof1]

How usefull a DDRS or passive system is? That actually has little to do with the circuit being high or low downforce, but more about how many straights there are and how long they are. In theory, and I say in theory, the concept will always have benefit: you can add additional downforce without a drag penalty. How large the benefit is depends on afore mentioned factors.
On Spa it is reckoned to have alot of advantage, especially Lotus their system since it will also shed drag at eau rouge. if n-smickles numbers are even remotely right it is something you want to have: you can reduce the AoA of the rear wing with it which would shed alot of drag, more then the 6% the VE adds.