The Kamm research cars

[JulianEdgar]

Originally Posted by aerohead

Yes, which brings us back to perspicacity.
Every element of the 'template' is spelled out by Hucho in a constellation of dots.
He provides the premise.
He provides the image.
He provides the empirically-derived quanta.
There is only one which embodies the drag minimum, in the context of an actual vehicle that a driver could see out of.
He explains the application.
We're talking about a 'basic' body, not a 'complex' body.
They're real alright.
And the future, if we want really low drag.

You know, each time I keep looking through Road Vehicle Aerodynamics 2nd edition, or more generally now reading the 5th edition, I keep looking for this stuff about the template - in the way you describe it and use it. It's simply not there - as others here have also commented.

(A constellation of dots indeed! What, like it needed to be hidden so only the chosen one would find it?)

Unfortunately, it's a theory that was developed by you, was largely uncritically accepted here, and has then caused all sorts of distorted 'understandings' of car aero to have developed among members of this group. It's clearest when someone pops in after an absence, happily embracing the template - and then suddenly looks around, and realises everyone is staring at them in an odd way. (Well, everyone who has done any investigations of their own, anyway.)

Anyone who uses the template - any of the templates, take your pick - for the following purposes is likely to be on very shaky ground indeed:

- Show where there is separated and attached flow on existing cars
- Guide the shape of rear extensions
- Show how rear spoilers on sedans should be positioned and shaped
- Allow the assessment of the ‘aerodynamic purity’ of cars

Unfortunately all these uses were being made here, if not on a daily basis, then certainly on a weekly basis.

[freebeard]

Unfortunately, it's a theory that was developed by you, was largely uncritically accepted here, and has then caused all sorts of distorted 'understandings' of car aero to have developed among members of this group.
...
Anyone who uses the template - any of the templates, take your pick - for the following purposes is likely to be on very shaky ground indeed...

You keep saying that. Not so.

And your four use cases ignore the Achilles Heel of The Template. The front/rear hemicircular aspect is as important as the side profile.

Nacelles, blisters and canopies....

[aerohead]

Originally Posted by JulianEdgar

You know, each time I keep looking through Road Vehicle Aerodynamics 2nd edition, or more generally now reading the 5th edition, I keep looking for this stuff about the template - in the way you describe it and use it. It's simply not there - as others here have also commented.

(A constellation of dots indeed! What, like it needed to be hidden so only the chosen one would find it?)

Unfortunately, it's a theory that was developed by you, was largely uncritically accepted here, and has then caused all sorts of distorted 'understandings' of car aero to have developed among members of this group. It's clearest when someone pops in after an absence, happily embracing the template - and then suddenly looks around, and realises everyone is staring at them in an odd way. (Well, everyone who has done any investigations of their own, anyway.)

Anyone who uses the template - any of the templates, take your pick - for the following purposes is likely to be on very shaky ground indeed:

- Show where there is separated and attached flow on existing cars
- Guide the shape of rear extensions
- Show how rear spoilers on sedans should be positioned and shaped
- Allow the assessment of the ‘aerodynamic purity’ of cars

Unfortunately all these uses were being made here, if not on a daily basis, then certainly on a weekly basis.

1) Since long before the pandemic showed up, I posted, exact quotes, and page numbers from the 2nd-edition, which fully illustrated the makings of the 'template.'
2) And I did it at least four times.
3) So here I am, many months later, and it appears that you've never given any effort to examine ANY of the data.
4) Four times!
--------------------------------------------------------------------------------------
What am I to make of such behavior?
--------------------------------------------------------------------------------------
You've been Johnny-on-the-spot as judge, jury, and executioner.
--------------------------------------------------------------------------------------
With an inspection of the material, every criticism of 'templates' fail.
-------------------------------------------------------------------------------------
The ability of the VW- Flow Body to predict Cd 0.14 is immediately accepted at face value, while the AST is rejected, wholesale, even though the VW-Flow Body, when compared, is essentially the AST!
--------------------------------------------------------------------------------------
The VW-Blunt Body ( solid border image ) is accepted immediately without question, even though it is virtually indistinguishable from the AST!
------------------------------------------------------------------------------------
Same with the VW-Drop Shape!
-------------------------------------------------------------------------------------
And we're absolutely deadlocked on the issue until you do what would be considered, normal due diligence.

[JulianEdgar]

Originally Posted by freebeard

You keep saying that. Not so.

That is based on what I observed here actually happening - not what may or may not have happened in years past.

And your four use cases ignore the Achilles Heel of The Template. The front/rear hemicircular aspect is as important as the side profile.

Sure, but again my comment is based on what I actually observed happening, as I said, at least weekly.

Nacelles, blisters and canopies....

Yes, any of the low drag shapes makes much more sense in those applications.

[JulianEdgar]

Originally Posted by aerohead

1) Since long before the pandemic showed up, I posted, exact quotes, and page numbers from the 2nd-edition, which fully illustrated the makings of the 'template.'
2) And I did it at least four times.
3) So here I am, many months later, and it appears that you've never given any effort to examine ANY of the data.
4) Four times!
--------------------------------------------------------------------------------------
What am I to make of such behavior?
--------------------------------------------------------------------------------------
You've been Johnny-on-the-spot as judge, jury, and executioner.
--------------------------------------------------------------------------------------
With an inspection of the material, every criticism of 'templates' fail.
-------------------------------------------------------------------------------------
The ability of the VW- Flow Body to predict Cd 0.14 is immediately accepted at face value, while the AST is rejected, wholesale, even though the VW-Flow Body, when compared, is essentially the AST!
--------------------------------------------------------------------------------------
The VW-Blunt Body ( solid border image ) is accepted immediately without question, even though it is virtually indistinguishable from the AST!
------------------------------------------------------------------------------------
Same with the VW-Drop Shape!
-------------------------------------------------------------------------------------
And we're absolutely deadlocked on the issue until you do what would be considered, normal due diligence.

This is what you do all the time. Take the existing argument, realise that you're not going to win on evidence, and so change the proposition to something else.

I have never said the template is not a low drag shape. I have never said that any of the templates are not low drag shapes.

These are all low drag shapes:



But that does not in any way lead to the idea that you can do any of the following with any of them:

- Show where there is separated and attached flow on existing cars
- Guide the shape of rear extensions
- Show how rear spoilers on sedans should be positioned and shaped
- Allow the assessment of the ‘aerodynamic purity’ of cars

They are simply low drag shapes, and the idea that (for example) you can pick one line from them, superimpose it over a completely different shape and then draw some inference from it is absurd.

The argument is not whether these shapes are low in drag. The argument is about the way you were encouraging their application here - to do things that are completely unjustifiable. In fact, quite wrong.

[aerohead]

Why are low drag shapes low drag?

[JulianEdgar]

Originally Posted by aerohead

Why are low drag shapes low drag?

That's not the argument.

The argument is how you were encouraging their use to purportedly achieve the following on existing cars:

- Show where there is separated and attached flow
- Guide the shape of rear extensions
- Show how rear spoilers on sedans should be positioned and shaped
- Allow the assessment of the ‘aerodynamic purity’ of cars

...and to do all of this often by picking just a tiny part of one of these shapes and placing it over the top of an existing car! Just crazy stuff - and not supported by any tech reference I've ever seen.

[orange4boy]

Today's episode of "Aerohead the Evil and the Template of Doom"

In my opinion, Julian Edgar is presenting a straw man argument about Template and that it presents some danger to a large group of people in order to then present himself as the saviour. He provides zero scientific evidence or proof of any kind of the veracity of his claims other than anecdotal stories reported by him. The template is a sticky on this website. That's about all you can say about it with any confidence that is relevant to any one member or any one discussion of aerodynamics.

He presents a series of four ambiguous statements. He claims these are wrong. He claims the template is used in these ways. That's a great strawman but where is the proof that so many people use it precisely in that way? Proof. Where is the proof? Anecdotes are not proof. "I saw the template used in this way" Is not proof. It's not even surface level convincing.

Where is your scientific study of the population of Ecomodder that believes these supposedly erroneous things. Do that work, then correlate that against their results in improving mileage or, better yet, jettison that and ask them if they give a flying frick about any of this.

"Julian Edgar thinks people are mislead by Aerohead." OK. Possible but improbable. Now prove it scientifically or STFU. Julian seems to love science and proof when it is convenient to him and ignores it when it isn't.

People may be mislead by many other things too. Like links provided by Julian Edgar that present lift erroneously as a result of "The air passing under the wing has further to travel than the air passing over the top surface."

Aerohead is free to post whatever he wants here and you are free to post whatever you want within the limits of civility.

Every single person here has a different take on the Template. Everyone is here for slightly different reasons.

Can we please, for the love of god, move on? Sorry, that's a rhetorical question. Of course not.

[freebeard]

Originally Posted by JulianEdgar

That is based on what I observed here actually happening - not what may or may not have happened in years past.
Sure...
Yes...

Thanks for finding agreement.

Picture Added 02-23-2014 11:58 AM



I used the template to:

- Show where there is separated and attached flow
- Guide the shape of rear extensions
- Show how rear spoilers boat tails on [Type I] should be positioned and shaped
- Allow the assessment of the ‘aerodynamic purity’ of [Type I]

edit:
This was reduced to practice in 2017

[JulianEdgar]

Originally Posted by orange4boy

Today's episode of "Aerohead the Evil and the Template of Doom"

In my opinion, Julian Edgar is presenting a straw man argument about Template and that it presents some danger to a large group of people in order to then present himself as the saviour. He provides zero scientific evidence or proof of any kind of the veracity of his claims other than anecdotal stories reported by him. The template is a sticky on this website. That's about all you can say about it with any confidence that is relevant to any one member or any one discussion of aerodynamics.

He presents a series of four ambiguous statements. He claims these are wrong. He claims the template is used in these ways. Proof. Where is the proof? Anecdotes are not proof. "I saw the template used in this way" Is not proof. It's not even surface level convincing.

If you'd been around here in the last year you'd have seen the template being used for every one of the ways I listed. That's why I made the list - otherwise the discussion just always went to generalities about template being good/bad, ignoring how it was actually being used.

Perhaps it wasn't being used like this when you were last here, but it certainly has been in the last year.

And the most important point seems to have been overlooked by you. And that's the theories and misunderstandings that people have developed from this completely fallacious notion of applying these shapes to existing cars.