Decimal places

[aerohead]

Originally Posted by AeroMcAeroFace

I can't find your third thread, but for everyone else, selected numbers are.

Total intake block cD change = -0.020

Baseline with 19" wheels = 0.249
19" aero wheels = 0.223
21" style wheels = 0.257

Depending on options specified, such as wheels, it is impossible to say 8% is the same for every option. But this test was done on the baseline model with 19" wheels and that, with all intakes blocked, reduced drag by 8%.

Would the same 0.02 change be found with the other wheels? Who knows? would the same 0.02 change be found on the myriad of numbers listed by aerohead, again we don't know.



Unfortunately true, I think it is a superiority issue, and good points/arguments get drowned out by the never ending gish gallop of aerohead.



Reading the referenced paper generally helps here.

In Julian's book he credits 'Tesla' with a Cd 0.26 attribution for the Model S.
'Tesla' also refers to a ' multi-stage active management of the cooling...', so, borrowing from Vman55, ' in what universe would you see a fixed cooling system drag coefficient, or percentage. '
Wouldn't it rather be, from zero to- 8%?
The Model S road load power requirement varies 460% between 85-mph and its top speed. In what universe would the cooling system drag be a 'constant'?
And then there's the issue of different drag coefficients.
Come on guys. Put your tin-foil caps on and see if you can do better.

[aerohead]

Originally Posted by JulianEdgar

Yeah, I am amazed that's its even a topic for debate - shows how much some people here lose the wood for the trees.

At minimum, it certainly shows how little contact some people here have with any science, physics, etc. Or even, just car modification generally?

' reckon you've never laid eyes on the CRC Handbook, and it's conversion tables.
Eight decimal places is not uncommon.
' guess it's only for people like Space X and Tesla Motors though.
Ford Motor Company shot for 326, and hit 201. And they expect you to pay $ 4,600 US for the shortfall.
I'll loan 'em my manual, free of charge.

[JulianEdgar]

Originally Posted by aerohead

In Julian's book he credits 'Tesla' with a Cd 0.26 attribution for the Model S.
'Tesla' also refers to a ' multi-stage active management of the cooling...', so, borrowing from Vman55, ' in what universe would you see a fixed cooling system drag coefficient, or percentage. '
Wouldn't it rather be, from zero to- 8%?
The Model S road load power requirement varies 460% between 85-mph and its top speed. In what universe would the cooling system drag be a 'constant'?
And then there's the issue of different drag coefficients.
Come on guys. Put your tin-foil caps on and see if you can do better.

The aerodynamicist responsible for leading the Tesla Model S program has checked my figure and was happy with it.

I don't need to "put on a tin-foil cap and see if I can do better".

I just ask the expert.

[aerohead]

Originally Posted by JulianEdgar

The aerodynamicist responsible for leading the Tesla Model S program has checked my figure and was happy with it.

I don't need to "put on a tin-foil cap and see if I can do better".

I just ask the expert.

So Palin's wrong.

[JulianEdgar]

Originally Posted by aerohead

So Palin's wrong.

Well I guess that's a pretty good summary of our different approaches.

I go to the true experts and get the best advice possible.

You make up your own theories and facts - and everyone else is apparently wrong.

But not surprisingly, professional car aerodynamicists know a bit more about the subject than Aerohead on Ecomodder does.

[aerohead]

Originally Posted by JulianEdgar

Well I guess that's a pretty good summary of our different approaches.

I go to the true experts and get the best advice possible.

You make up your own theories and facts - and everyone else is apparently wrong.

But not surprisingly, professional car aerodynamicists know a bit more about the subject than Aerohead on Ecomodder does.

Perhaps we have another nomenclature situation.
Next time you visit with Palin, can you ask him how he defines the term ' multi-stage'?
In light of variable-speed cooling fans, and variable-pitch radiator shutters, I may be misinterpreting what he means by 'multi'. If it has to do the the Octovalve, and internal coolant flow rates and flow diversions, then that's a non-aerodynamic issue.

[JulianEdgar]

Originally Posted by aerohead

Perhaps we have another nomenclature situation.
Next time you visit with Palin, can you ask him how he defines the term ' multi-stage'?
In light of variable-speed cooling fans, and variable-pitch radiator shutters, I may be misinterpreting what he means by 'multi'. If it has to do the the Octovalve, and internal coolant flow rates and flow diversions, then that's a non-aerodynamic issue.

Why don't you just go and read the SAE paper on the car?

Oh I forgot. Far better to just make up stuff here rather than actually go to the source that I quoted and read it.