The P word strikes again

[V8 Fireworks]

Originally Posted by Spec83

I wonder if these Supercars snoozers know this place exists: https://www.monash.edu/engineering/o...unnel-facility

50 m/s = 180 km/h

VCAT currently defines the figure at 200 km/h I understand, so only a small adjustment needs to be made to equate it to match the tunnel vmax


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Monash wind tunnel doesn't have a rolling road (moving floor belt) which is necessary for accurate automotive testing.

It's necessary because fluid is *always" stationary immediately adjacent to a physical surface (like a road), called the "no slip" condition. There is the so called "boundary layer" where the fluid speed transistions from zero to the outer air speed. This boundary layer can be tens of cm thick at an automotive scale, so it's important to model it accurately. It's also important the vehicle's wheels are actually turning at the proper rate too (for the same reason of fluid always having no slip at solid boundaries like a rotating tyre).

They would be better off using the Pinnifarina or Wind Shear wind tunnels which are setup for full scale automotive testing with rolling roads.

[Tourer]

Originally Posted by Forda

The truth is, however, the Mustang was ultimately and unfairly penalised last year, simply due to Scotty's freakish talent.
No other Mustangs were able to really get near him, not even his own teammate in an identical car.

Let's not talk about Mr Waters then, got a bit too near Scotty a couple of times there!

No question that Mr McLaughlin is talented but the judgements on technical changes to the different cars weren't based on race results of a single car but on data collected from a wider group than that, using CFD and of course the now famous CoG testing.

I know that you didn't like the changes happening at the time and regard them still as unfair but it is a parity series and has always been so. Hopefully the improved VCAT regime will result in no changes being necessary through the course of the upcoming season but if the data shows that changes for parity are needed, then we may see them again.

[Spec83]

Originally Posted by V8 Fireworks

Monash wind tunnel doesn't have a rolling road (moving floor belt) which is necessary for accurate automotive testing.



It's necessary because fluid is *always" stationary immediately adjacent to a physical surface (like a road), called the "no slip" condition. There is the so called "boundary layer" where the fluid speed transistions from zero to the outer air speed. This boundary layer can be tens of cm thick at an automotive scale, so it's important to model it accurately. It's also important the vehicle's wheels are actually turning at the proper rate too (for the same reason of fluid always having no slip at solid boundaries like a rotating tyre)

You learn something new every day, thank you :-)

Oh... apologies for the double post, new around here and getting to grips with the app!!




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[Tourer]

Originally Posted by Casper

Call me sceptical, running a car down an airstrip does not sound like a very definitive test to me. How can they duplicate conditions closely enough is one of life's little mysteries, even the air temp and barometric pressure would induce bad reporting let alone anything else like tight or loose wheel bearings, rising tyre pressures and even with nitrogen they do vary, how well the car was polished and most probably a hundred other things as well. They should run them off the top of Conrod in neutral and see how far they roll out, far quicker and just as accurate?

You're sceptical

From the first time TEGA did one of these airstrip tests (back in 2000) a lot of those variables you mention were thought through and accounted for by various means with input from the tech boffins working for teams. Last year it became evident that the process hadn't been upgraded enough over the years since 2000 and it now has been, we'll find out this season if it stands up.

Conrod isn't even close to long enough or flat enough for consistency - airstrips are used due to being much longer - it is the coast down to zero that takes the distance and based on the length of the airstrips used, the coast down would have the cars rolling into the city centre of Bathurst.

Originally Posted by Spec83

I wonder if these Supercars snoozers know this place exists: https://www.monash.edu/engineering/o...unnel-facility

V8 Fireworks answered this one for you - not the "snoozers" you thought huh?

F1 teams use airstrip coast down tests to this day as a means of "verifying" wind tunnel results in the real world. Not everything developed in the tunnel survives scrutiny at the airstrip testing and makes it onto the cars for racing.

Ultimately, a wind tunnel is a tool, not an absolute and the results generated do not necessarily get replicated in the real world but if Supercars DID want to run some wind tunnel tests, it would need to fly the cars overseas and then still do the coast down tests to verify the wind tunnel tests.

So far, no-one there has been able to justify the cost of doing that but it could happen one day.

[Forda]

Originally Posted by Tourer

Let's not talk about Mr Waters then, got a bit too near Scotty a couple of times there!

And his 7th place in the championship?

Originally Posted by Tourer

No question that Mr McLaughlin is talented but the judgements on technical changes to the different cars weren't based on race results of a single car but on data collected from a wider group than that, using CFD and of course the now famous CoG testing.

That might be the official narrative; but geeze, have you ever smelled what you're shoveling?

Originally Posted by Tourer

I know that you didn't like the changes happening at the time and regard them still as unfair but it is a parity series and has always been so.

History clearly shows they got it totally wrong, and then continued to do so, repeatedly, in a reactive and half-cocked manner.

Originally Posted by Tourer

Hopefully the improved VCAT regime will result in no changes being necessary through the course of the upcoming season but if the data shows that changes for parity are needed, then we may see them again.

Not much hope I'm afraid, given the precedent which has already been set.

[Mixer]

If you idiots think Roger Penske is going to spend nearly $20m big ones a year, and just lay down and allow the series THAT HE PART OWNS to disadvantage him as some sort of conspiracy, you are a crackpot and quite obviously can't think clearly.

****ing comical all the T8$ crap when there is a multi-BILLIONAIRE with resources, nous and form for pushing the boundaries beyond the entire rest of the field put together behind Penske.

[bluesport]

Judging by how fast the T8 commodores were at seasons end there can be little doubt that they were sandbagging earlier in the championship to get changes before Bathurst.

[Umai Naa]

It's a clean slate.

[Casper]

Originally Posted by Tourer

You're sceptical

From the first time TEGA did one of these airstrip tests (back in 2000) a lot of those variables you mention were thought through and accounted for by various means with input from the tech boffins working for teams. Last year it became evident that the process hadn't been upgraded enough over the years since 2000 and it now has been, we'll find out this season if it stands up.

Sceptical, what would make you say that? You can't change physics so lets put that in big capital letters so everyone can see it. The physics have not changed because they can't change so the process by their own admission has been flawed from day 1. What is a tech boffin...he is someone who tries to work the system to advantage his team and they let these guys loose with the rules? This process has to be crudest way to make anything equal to anything that I can think of and the results and admissions show it.

This is a professional race series so why not use professional methods to implement parity? If money is the problem then something is very wrong because a well founded series would have it.

[Mixer]

Originally Posted by bluesport

Judging by how fast the T8 commodores were at seasons end there can be little doubt that they were sandbagging earlier in the championship to get changes before Bathurst.

Yeah that's why all the cars including the Nissans were like 2 seconds a lap faster at Bathurst... because the Commodores were sandbagging...

[Umai Naa]

Triple Eight are always strong in the back half of the season. Has been that way for a long time.

[Tourer]

Originally Posted by Casper

Sceptical, what would make you say that?

Because you said "call me sceptical" in your previous post

Originally Posted by Casper

This process has to be crudest way to make anything equal to anything that I can think of and the results and admissions show it.

This is a professional race series so why not use professional methods to implement parity? If money is the problem then something is very wrong because a well founded series would have it.

Still used by F1 teams now and "real world" rather than "crude" & still professional - after using it for 20 years the results have been good until the last season, which showed that the process needed to be updated, which it has been.

We'll see if it has delivered during 2020.

[Mark Petch]

Originally Posted by Tourer

Because you said "call me sceptical" in your previous post

Still used by F1 teams now and "real world" rather than "crude" & still professional - after using it for 20 years the results have been good until the last season, which showed that the process needed to be updated, which it has been.

We'll see if it has delivered during 2020.

Well said Tourer.

[Mixer]

Originally Posted by Tourer

Because you said "call me sceptical" in your previous post



Still used by F1 teams now and "real world" rather than "crude" & still professional - after using it for 20 years the results have been good until the last season, which showed that the process needed to be updated, which it has been.



We'll see if it has delivered during 2020.

BANG ON.

F1 teams validate their wind tunnel work, with coastdown tests and straight line running.

Adrian Burgess is ex F1, as is Tim Edwards and probably others. They know way more than a bunch of monkeys on keyboards that wouldn't know a wind tunnel from the sock in their bottom drawer.

[Jerico]

A side note to the parity talk. Evidently the 17 car had the only chassis built stateside. Not sure of the origins of the replacement chassis late season? But expect it also was built stateside? In pre season testing of the new Mustang the 17 chassis was consistently faster than that of car 12, regardless of who the shoe was.

If you need an example of what difference a car can make to a driver I have two words for you, Garth Tander. Years of mediocre and underwhelming results to last year's outstanding performance.

[Mixer]

I believe Penske wanted to build chassis overseas but it was disallowed. Put Scotty in Fabs car and he would rip it up.

[Jerico]

Yeah Scott would have still been fast in car 12. regardless of where the chassis was built car 17 was the fastest of the two in testing. Look at the season and it's clear Scott did less winning in the second half of the championship. Did he lose his edge or did his car? No argument from me that Scott is fast. Hell he's been put up with the all time greats of the sport after two championships and a Bathurst win.

[Umai Naa]

The cars can't be built overseas, as they need to be inspected at numerous built stages during construction, for compliance.

[Backagain]

Originally Posted by Umai Naa

The cars can't be built overseas, as they need to be inspected at numerous built stages during construction, for compliance.

Correct, they cannot be built overseas, Scotty started loosing races only after several "adjustments" to the Mustangs and Commodores to retain the favoured status quo.

[Compromised]

All I'm getting out of the latest VCAT is the Mustang had an unfair advantage in 2019, up to and including the last few races and only now is it rectified (otherwise no changes would have been necessary).

So essentially a whole season of Holden based competitors being shafted.

[Mixer]

Latest VCAT is reducing downforce by 15%.

[Forda]

Originally Posted by Backagain

Scotty started loosing races only after several "adjustments" to the Mustangs

Or to put it another way, 888 started dominating/stopped foxing once they had their aero update approved outside the commission, just prior to the Auckland round.

Originally Posted by Backagain

and Commodores to retain the favoured status quo.

Exactly.

Originally Posted by Mixer

Latest VCAT is reducing downforce by 15%.

Speedcafe are reporting an approximate 12% reduction, and AA a 10-12% reduction in downforce; with revisions being minor for the Opel, and more extensive for the Mustang (including a re-location of the rear wing).

[Mixer]

Originally Posted by Mixer

Yeah that's why all the cars including the Nissans were like 2 seconds a lap faster at Bathurst... because the Commodores were sandbagging...

Nissan and Commodore didn't go so fast at Bathurst because 888 stopped sandbagging, it is because they got closer to the Mustang. But not so close that anybody could pass one.

[Forda]

Originally Posted by Mixer

Nissan and Commodore didn't go so fast at Bathurst because 888 stopped sandbagging, it is because they got closer to the Mustang. But not so close that anybody could pass one.

Nissan received a benefit as a byproduct of 888 looking after their own interests, first and foremost.

As Nissan were never going to be an outright threat to anyone, the whole situation worked out well for 888.

[Umai Naa]

That was all last year.

Let's talk about this year.