2019 Mclaren F1 Team - Renault

[_cerber1]

Guys just a quick reference to Mexico- we know that historically Red Bull did very well there with Renault power and Horner mentioned how the high altitude essentially took away the Merc and Ferrari advantage on power. Does this bode well for McLaren this weekend?

However, I also read that really in Mexico despite the straights, “downforce is king” in that level of altitude, which RBR have always been brilliant with.

So is it one, the other, or a mix of those two factors to consider?

They promise rains during the race weekend, all this can turn into a lottery.

[bauc]

Guys just a quick reference to Mexico- we know that historically Red Bull did very well there with Renault power and Horner mentioned how the high altitude essentially took away the Merc and Ferrari advantage on power. Does this bode well for McLaren this weekend?

However, I also read that really in Mexico despite the straights, “downforce is king” in that level of altitude, which RBR have always been brilliant with.

So is it one, the other, or a mix of those two factors to consider?

They promise rains during the race weekend, all this can turn into a lottery.

Who are they?

[Ground Effect]

Guys just a quick reference to Mexico- we know that historically Red Bull did very well there with Renault power and Horner mentioned how the high altitude essentially took away the Merc and Ferrari advantage on power. Does this bode well for McLaren this weekend?

However, I also read that really in Mexico despite the straights, “downforce is king” in that level of altitude, which RBR have always been brilliant with.

So is it one, the other, or a mix of those two factors to consider?

Vandoorne managed to be eight with a car that wasnt updated for months and had a fatal flaw. They might be good here, but reliability is a questionable.

Yep, captain slow had a strong race to finish 8th. Fernando qualified 12th, Renault works team qualified best of the rest, with Hulk finishing 6th. Red Bulls locked the front row, with Max winning. So it’s safe to say the Renault PU had some sort of advantage.

[izzy]

Guys just a quick reference to Mexico- we know that historically Red Bull did very well there with Renault power and Horner mentioned how the high altitude essentially took away the Merc and Ferrari advantage on power. Does this bode well for McLaren this weekend?

According to Mark Hughes the Renault engine has a relatively small turbo that they can turn up more, because generally the others can't get to the 120k regulation limit without bursting apart. If it's small i don't see why it's not turned up already at sea level but that's what he said, and as you say the Renault engine has looked better in Mexico, so let's just hope it's reliable

[FittingMechanics]

Guys just a quick reference to Mexico- we know that historically Red Bull did very well there with Renault power and Horner mentioned how the high altitude essentially took away the Merc and Ferrari advantage on power. Does this bode well for McLaren this weekend?

According to Mark Hughes the Renault engine has a relatively small turbo that they can turn up more, because generally the others can't get to the 120k regulation limit without bursting apart. If it's small i don't see why it's not turned up already at sea level but that's what he said, and as you say the Renault engine has looked better in Mexico, so let's just hope it's reliable

My understanding was that the others are operating at the limit of their turbo, so when the air is less dense they cannot spin the turbo faster to compress the air to a level they normally get at sea level. Renault is apparently further away from the limit, can spin the turbo fast enough to compress the air to a level they normally get at sea level, and thus lose less power at altitude.

Reason why Renault is not spinning faster at sea level is that they are not limited by amount of compressed air going into the engine.

[izzy]

My understanding was that the others are operating at the limit of their turbo, so when the air is less dense they cannot spin the turbo faster to compress the air to a level they normally get at sea level. Renault is apparently further away from the limit, can spin the turbo fast enough to compress the air to a level they normally get at sea level, and thus lose less power at altitude.

Reason why Renault is not spinning faster at sea level is that they are not limited by amount of compressed air going into the engine.

Yes that's correct, sorry i took that as understood. Tho it doesn't explain why the Renault engine has this headroom, unless they are in fact limited at sea level. That would imply they can't flow as much air through the engine as the others, normally, if their small turbo has this spare capacity. Or, i suppose, their turbo is more efficient somehow and can easily keep up with the fuel flow at sea level, but that would be a bit of a surprise considering who they're up against

[Jackles-UK]

I was under the impression that the Red Bull dominance in recent years was due to higher downforce being able to more effectively harness the thinner air hitting the car at altitude as opposed to the Renault engine playing a big part. Horner said that it levels the playing field because it trims the top-end power advantage to a point where others can compete rather than where the ball is in their court.

Don’t forget that 3 of the 4 retirements last year were Renault engined cars (although Fernando was admittedly a victim of contact ahead of him), Riccardo and Sainz both retired with Renault malfunctions from big points paying hauls.

[littlebigcat]

I would assume with Ferrari's supposed advantage being their ERSs, that this advantage would only be exaggerated compared to the Renault engine

[JRindt]

Yes that's correct, sorry i took that as understood. Tho it doesn't explain why the Renault engine has this headroom, unless they are in fact limited at sea level. That would imply they can't flow as much air through the engine as the others, normally, if their small turbo has this spare capacity. Or, i suppose, their turbo is more efficient somehow and can easily keep up with the fuel flow at sea level, but that would be a bit of a surprise considering who they're up against

In a naturally-aspirated engine, the thinner air directly reduces the power potential. With less air to burn it cannot achieve the same force of explosion within its combustion chambers. However, turbocharged engines such as those currently used in F1 do not suffer this effect directly because the pressure of the air fed to the combustion chamber is controlled by the turbo. A lower density of air allows the turbo to simply spin faster to achieve the same air pressurisation (and therefore density) as at sea level.

But there are complications. Each of the four engines has an official turbine ‘burst point’ – the maximum speed at which it is safe and at which a failure would not result in the bursting of the turbo casing and the spreading of high-velocity debris all over the track. This burst point speed of each engine design is verified and homologated and provided to the FIA. The turbos cannot be run beyond this speed, regardless of the regulated limit of 120,000rpm. That simply means if the burst speed could be made as high as 120,000rpm, they would be allowed to run at that. But the burst speed is usually below that limit.

As a general rule, the bigger the turbo the lower its burst speed will be.

Historically in this formula, Mercedes have favoured the biggest turbos; Renault the smallest. The sizing of the turbo is generally determined by how efficient the energy transfer is from the turbine to the crankshaft via the electronics and MGU-K. A less efficient system suffering greater losses will be less able to justify the extra cooling, volume and weight of a bigger turbo than a more efficient system. So in general terms, the more efficient the energy transfer is within the turbo compound loop, the bigger the turbo that can be justified. At conventional altitudes, this will tend to be a better performing engine.

However, if the altitude is such that in turning harder to compensate for the thin air, it takes the turbo close to its burst point, then that engine might be disadvantaged to one with a smaller turbo and higher burst point speed. Historically, the Renault has been a very competitive engine in Mexico City. Where the current four designs all figure at Mexico will be intriguing.

https://www.formula1.com/en/latest/arti ... VjIoq.html

[RonDennis]

No appeal from Renault, so I think it's clear to say that McLaren will end 4th.

https://www.motorsport.com/f1/news/rena ... n/4585513/

[Bill]

According the Vettel last year Renault has a big turbo the biggest among the four manufacturers so at high altitude is not a handicap. Teams with split turbo natural has a small turbo I.e. Honda and Mercedes. At high high altitude a small turbo spins at high speed to compensate for low air density and that brings other technical challenges.

[JRindt]

According the Vettel last year Renault has a big turbo the biggest among the four manufacturers so at high altitude is not a handicap. Teams with split turbo natural has a small turbo I.e. Honda and Mercedes. At high high altitude a small turbo spins at high speed to compensate for low air density and that brings other technical challenges.

According to F1 official website, Renault have the smallest turbo and Mercedes have the biggest. Not surprising considering Renault's performance over the years, since smaller turbos are associated with lower efficiency at normal altitudes. However, it remains to be seen how this year's engines fare.

[Jolle]

According the Vettel last year Renault has a big turbo the biggest among the four manufacturers so at high altitude is not a handicap. Teams with split turbo natural has a small turbo I.e. Honda and Mercedes. At high high altitude a small turbo spins at high speed to compensate for low air density and that brings other technical challenges.

A split turbo has less of a size constraints then non split turbos I think, especially the compressor because it’s all “free” at the front of the engine.

Turbos have a max rev set by the rules (well, the MGU-H has) of 125k rpm, so not much play here, if you’re already on that number on sea level.

[f1rules]

fabrega, who else meassuering flow on the rear part of the floor ala merc used in the past,

[izzy]

Historically in this formula, Mercedes have favoured the biggest turbos; Renault the smallest. The sizing of the turbo is generally determined by how efficient the energy transfer is from the turbine to the crankshaft via the electronics and MGU-K. A less efficient system suffering greater losses will be less able to justify the extra cooling, volume and weight of a bigger turbo than a more efficient system. So in general terms, the more efficient the energy transfer is within the turbo compound loop, the bigger the turbo that can be justified. At conventional altitudes, this will tend to be a better performing engine.

yes that's what i read. Must admit my mind went a bit blank reading this bit and i'd forgotten! Where do the losses occur? isn't it all AC? also it's not a great sign is it, in terms of Renault staying in F1 and winning eventually, with apparently outsourcing everything at Viry too. And it's the kind of thing McLaren would know