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Old 11-11-2020, 05:02 PM   #131 (permalink)
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The joke kinda fell in my lap.

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Old 11-12-2020, 01:37 PM   #132 (permalink)
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Quote:
Originally Posted by aerohead View Post
I dug out what I have on P.W. Bearman and brought it with me. I've had Hummel with me for the last 9-months or so.
We can better discuss it now if you like, however you may regret it. It's very pro-template, and extremely counterfactual to some of your 'modern' contemporary aerodynamic assertions.
Calm down; I wasn't attacking you and you don't need to make threats. I was merely responding to this claim:

Quote:
1) Most of the 'flow' on an automobile is 'laminar.'
Which you then corrected in your next post anyway:

Quote:
* Due to the 'size' of an automobile, once to 20-mph, it's going to be fully immersed in a turbulent boundary layer. And it's Cd constant up to 250-mph.
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Old 11-13-2020, 11:50 AM   #133 (permalink)
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laminar

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Originally Posted by Vman455 View Post
Calm down; I wasn't attacking you and you don't need to make threats. I was merely responding to this claim:



Which you then corrected in your next post anyway:
From my archive, automotive rolling stock at the time of Bearman's July 23, 1979 REVIEW in the Journal of Fluid Engineering, possessed drag coefficients ranging from Cd 1.15, to Cd 0.178. Nearly the full spectrum.
It would have been impossible to make any all-encompassing, blanket statement about flow around automobiles.
In April 1977, Glenn D. Thompson of the EPA came out in favor of the 'template'.
Bearman's 1979 article eluded to the 'template' with his comment, ' where the boundary layer fails to withstand some critical adverse pressure gradient.'
Bearman goes on to share W.A. Mair's boat-tail schematic, with it's specific lead-in contour transitioning to the recommended maximum 22-degree slope angle ( the model for the aerodynamic streamlining template number-one ). Mair's data reflects only pressure drag. Viscous effects have been removed from the presentation. It has nothing to do with the viscous boundary layer, or boundary layer thickness.
The EPA's 1977 contour is the aerodynamic streamlining template number two.
Bearman goes on to describe the mirror-image, ground reflection from potential flow theory which explains Jaray's 1922, Cd 0.13, half- ( Zeppelin ) body automobile, which also pre-quantifies the drag of the 'template', as it's drag was published in 1923 by Prandtl, originator of both the Sch'o'rwagen, and 'Lange' car.
In Bearman's preamble to his 1979 review he speaks of 'complex' body shapes of which flow would be difficult to predict. No objection to that. The 'template', however is a simple, non-complex body. It is streamlined. It's a known quantity. There's nothing abstract or hypothetical about it. It's in perfect agreement with boundary layer theory. And it's exactly what Hucho is speaking to in relation to a path forward towards sub- Cd 0.10 automobiles. It's not a matter of technical feasibility. It's not a conspiracy theory.
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Old 11-13-2020, 02:22 PM   #134 (permalink)
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The 'template', however is a simple, non-complex body. It is streamlined. It's a known quantity. There's nothing abstract or hypothetical about it. It's in perfect agreement with boundary layer theory. And it's exactly what Hucho is speaking to in relation to a path forward towards sub- Cd 0.10 automobiles. It's not a matter of technical feasibility. It's not a conspiracy theory.
It's a Procrustean Bed. Alter you use case and submit.
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Old 11-13-2020, 02:47 PM   #135 (permalink)
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arbitrary forcing

Your comment remains so obtuse I can make nothing of it. Wanna help me out here?
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Old 11-13-2020, 03:15 PM   #136 (permalink)
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Happily.
Quote:
It's a Procrustean Bed*. Alter you** use case and submit***.
*https://en.wikipedia.org/wiki/Procrustes
Quote:
A Procrustean bed is an arbitrary standard to which exact conformity is forced.. In Edgar Allan Poe's influential crime story "The Purloined Letter" (1844), the private detective Dupin uses the metaphor of a Procrustean bed to describe the Parisian police's overly rigid method of looking for clues.;
**Typo: 'you' for 'your'.

***('Respect My Authoritah' — Cartman)

Long story short, The Template is perfect for transporting liquids because they assume the shape of their container.
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Old 11-13-2020, 04:00 PM   #137 (permalink)
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arbitrary

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Happily.


*https://en.wikipedia.org/wiki/Procrustes


**Typo: 'you' for 'your'.

***('Respect My Authoritah' Cartman)

Long story short, The Template is perfect for transporting liquids because they assume the shape of their container.
Why the use 'arbitrary' in relation to this conversation?
When I get paid 6-figures for my at -my -own -cost volunteer work, I'll have a secretary cover my typos.
The template is not a vessel for transporting liquids. It's a fully-submerged body.
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Old 11-13-2020, 05:24 PM   #138 (permalink)
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Quote:
Why the use 'arbitrary' in relation to this conversation?
Wikipedia's word choice, not mine. Maybe read The Purloined Letter?

Six figures? Make it so. I'd work for five.

The Template is more suited to transporting cow milk than it is concrete blocks.

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