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Deletedmember130310
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Williams technical chief Paddy Lowe officially leaves team - no great surprise...
Williams technical chief Paddy Lowe officially leaves team
Williams technical chief Paddy Lowe officially leaves team
F1 2019
- Thread starter Stratman
- Start date
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Deletedmember130310
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Didn't Toto Wolff have some involvement, as large shareholder, in Williams not so long ago? I wonder what prompted him to invest in, and manage, the MB team taking over from Norbert Haug
Bellow
Hardcore MB Enthusiast
Without wanting to steer the thread too far off course.... re tyre profile heights - which has the lower rolling resistance?
(Accepted that lo-pros usually adversely affect fuel consumption (road car) which the increased (polar) inertia (and sometimes greater aero drag if tyre is wider) is usually (and correctly) blamed. Where does rolling resistance figure though. Feels counter intuitive to believe lo-pro has higher RR - has it?)
(Accepted that lo-pros usually adversely affect fuel consumption (road car) which the increased (polar) inertia (and sometimes greater aero drag if tyre is wider) is usually (and correctly) blamed. Where does rolling resistance figure though. Feels counter intuitive to believe lo-pro has higher RR - has it?)
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How would low profile tyres cope with the massive changes in down-force the tyres experience?
Probably not a lot in it for tyres of the same width. I wouldn't be surprised if having some sidewall compliance helps with rolling resistance as some tyre distortion is required. Even steel train wheels flex when they roll along.
Rolling resistance on tarmac is typically 0.013 x 9.81 x Vehicle Mass (kg) = Rolling Drag (N) and comes out at around 150N for a typical car. It's not (in theory) speed dependent so is treated as a constant value added to the road-load model. At low (constant) speeds it makes up the biggest part of the drag forces acting on the car. Above about 100km/h, aerodynamic drag forces start to dominate with differences in rolling resistance being less important.
The answer is slightly better. F1 is out on a limb with 13" rims, and whilst the tyres can be made to work, it would be technically much preferred to have less of an undamped spring spring and more control of the ride height.
Since the 80's most other race cars other than single seaters have homed in on 18" rims as the best compromise. Sports and touring cars have flirted with larger and smaller rims, but now almost all GT, sports and touring cars are on 18's.
Le Mans car are heavier and can have more downforce than F1 cars.
Rolling resistance? That is almost completely tyre dependant. Given the same width and pressure it is the tyre construction and not the profile that defines the rolling resistance of a tyre of similar overall diameter. The overall mass of the wheel/tyre combo has an effect during accel and deccel, but at constant velocity, it is very small.
The other thing with rolling resistance is that the standard calculation outlined above doesn't take into account aerodynamic downforce, which must be added. So for a racing car that produces significant downforce, the rolling resistance increases with speed inline with the increase in downforce.
With stiffer sidewalls, the forces are transferred more directly to the road surface. Should provide a better more controllable aero platform.
With stiffer sidewalls, the forces are transferred more directly to the road surface. Should provide a better more controllable aero platform.
Yes, tyre technology is often referred to as a 'black art'. It isn't. It's a very complex science.
There are just so many factors which have to be taken in to account to model a tyre correctly. For instance:
Even before we get to tyre, it's environment can have a huge effect.
Diameter of rim not only has a an effect of the size of the sidewall and the vertical stiffness but also the volume of gas in the tyre
The rim type can also radically change the volume of gas. This impacts the change in stiffness for a given vertical load.
Width of the rim. For the same tyre, it will dramatically change the way the tyre feels change of direction due to the change in presentation angle of the sidewall to the tread.
Construction is the most complex of all, and has millions of permutations, that's before we get to any car geometry, temperature change to the pressure, construction and the compound grip.....
Maybe without the use of a super computer, a lot of clever programmers, intuitive race engineers and great drivers....it will remain a black art
There are just so many factors which have to be taken in to account to model a tyre correctly. For instance:
Even before we get to tyre, it's environment can have a huge effect.
Diameter of rim not only has a an effect of the size of the sidewall and the vertical stiffness but also the volume of gas in the tyre
The rim type can also radically change the volume of gas. This impacts the change in stiffness for a given vertical load.
Width of the rim. For the same tyre, it will dramatically change the way the tyre feels change of direction due to the change in presentation angle of the sidewall to the tread.
Construction is the most complex of all, and has millions of permutations, that's before we get to any car geometry, temperature change to the pressure, construction and the compound grip.....
Maybe without the use of a super computer, a lot of clever programmers, intuitive race engineers and great drivers....it will remain a black art
I was very surprised to read of a study that showed for a given load, wider tyres actually reduced rolling resistance and that the improvement more than offset the increased aerodynamic drag. It sounds completely counter intuitive but perhaps the different shape of the contact patch produces less internal friction. Still it makes a puzzle of why MB fitted narrow tyres to some Blue efficiency models. If the tyre width is increased by 10mm on my car it pushes it up into the next road fund tax bracket through increased CO2 emmisions.
I wonder which is correct.
Barry's Tire Tech
Again, I think so much depends on the tyre construction. If constructors use a similar construction on a range of sizes of the same tyre, there is bound to be a variation in which is the 'best' size for that specific construction.
On my GLE I have gone from 265/45/20 Pirelli to 275/45/20 Avon. I honestly can not see any difference in fuel consumption, indicating little change in rolling resistance.
I can demonstrate improved kerb strike protection, a 2dba reduction in cabin noise at 70mph on my reference road, improved wet and dry grip, a perceived ride quality improvement and a reduced cost to me of £240 for the 4 tyres. That's about 3 fill ups of fuel.
I will have little 'rolling resistance' to buying another set when these have done a their currently projected 30k miles!
On my GLE I have gone from 265/45/20 Pirelli to 275/45/20 Avon. I honestly can not see any difference in fuel consumption, indicating little change in rolling resistance.
I can demonstrate improved kerb strike protection, a 2dba reduction in cabin noise at 70mph on my reference road, improved wet and dry grip, a perceived ride quality improvement and a reduced cost to me of £240 for the 4 tyres. That's about 3 fill ups of fuel.
I will have little 'rolling resistance' to buying another set when these have done a their currently projected 30k miles!
Bellow
Hardcore MB Enthusiast
Depending on the nature of the road, higher cornering speeds can give back anything lost RR or aero drag. Never a level playing field!
Bellow
Hardcore MB Enthusiast
Going back to the James Allison piece.
I was surprised by how little movement there is in F1 suspension (5mm!). Obviously that is controlled by very stiff springs that must have the suspension nearly locked solid. At that point - is it still suspension or a rigid system? Is the roll centre location (for that axle) still a function of the intersection of the lines drawn through the pivots or solely at the outer tyre's contact patch?
More generally, in lesser (read road cars), if the above is true, at which point during roll does the contribution to roll centre location cease to be affected by the inner wheel (eg, how can an airborne wheel contribute anything?)? The text books only deal with the static case and mention the RC moves in cornering, but still the implication is that it does so in accordance with the geometry of the links alone and never mentions any proportionality caused by weight transference - the very thing roll centres are supposed to control.
I was surprised by how little movement there is in F1 suspension (5mm!). Obviously that is controlled by very stiff springs that must have the suspension nearly locked solid. At that point - is it still suspension or a rigid system? Is the roll centre location (for that axle) still a function of the intersection of the lines drawn through the pivots or solely at the outer tyre's contact patch?
More generally, in lesser (read road cars), if the above is true, at which point during roll does the contribution to roll centre location cease to be affected by the inner wheel (eg, how can an airborne wheel contribute anything?)? The text books only deal with the static case and mention the RC moves in cornering, but still the implication is that it does so in accordance with the geometry of the links alone and never mentions any proportionality caused by weight transference - the very thing roll centres are supposed to control.
Agreed, but my best point of reference over a number of times of a trip I do regularly in a variety of climatic and traffic conditions. It's the best I can do with out my own private test track
Bellow
Hardcore MB Enthusiast
Agreed, but my best point of reference over a number of times of a trip I do regularly in a variety of climatic and traffic conditions. It's the best I can do with out my own private test track
I was more trying to say that some losses may be be countered by the higher cornering speed as a matter of design so to speak. If the roads being used are sufficiently twisty, wider rubber can work in our favour even if the RR and aero losses are higher.
To truly test though, not so much a test track needed as a perfectly straight stretch of tarmac several hundred miles long - if such a thing exists - and a deal of patience.
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Lewis gets 3 place grid penalty for impeding Kimi. Can't remember the last time the grid was so mixed up. So, grid will start
1. LeClerc
2. Verstappen
3. Bottas
4. Magnussen
5. Hamilton
Lewis Hamilton drops to fifth on Austrian GP grid after penalty
1. LeClerc
2. Verstappen
3. Bottas
4. Magnussen
5. Hamilton
Lewis Hamilton drops to fifth on Austrian GP grid after penalty
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Haven't watched Qually yet, but if Lewis blocked/affected Kimi's lap, then a 3-place penalty is right. Others got penalised, so should Lewis.
Will be interesting to see if LeClerc can bring one home.
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Lando Norris up to 4th as Magnussen drops 5 places for a gearbox change.
Austrian Grand Prix: Charles Leclerc powers to pole as Lewis Hamilton demoted
Yes, both Brits Lewis and George Russell were caught out by the short circuit and bunching of the cars. They both put their hands up to the 'crimes' and were both penalised according to the regulations. In mitigation, car a on a lap were traveling at twice the speed as cars cruising and the view in F1 car mirrors is not the best.
Weirdest fact of all is that on this particular circuit they were all looking for tows rather than finding space as the deficit of following a car in high speed turns (there are very few) was more offset by getting a draft on the straights!
Weirdest fact of all is that on this particular circuit they were all looking for tows rather than finding space as the deficit of following a car in high speed turns (there are very few) was more offset by getting a draft on the straights!
