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Old 05-15-2020, 11:24 AM   #41 (permalink)
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Quote:
Originally Posted by aerohead View Post
On page 22,Fig.1.12.,of Hermann Schlicting's 'Boundary-Layer Theory',you'll find a complete pressure profile of a streamline body,presented originally by Fuhrmann.
You'll notice the positive static pressure acting on both the nose and tail,allowing for zero lift.
On page 23,Fig.1.14. you'll find a complete pressure profile of a Zhukovskii wing section,demonstrating a zero-lift condition (just as the 118-families of wing sections listed in Theory of Wing Sections) ,after the research of A. Betz.
If 'the exception proves the rule',then,when you make statements about the existence of lift for wings and streamline bodies,you'll want to include all the qualifying caveats/conditions.
Caveats and conditions is what one comes to understand better through practical experience, more study, more practical experience... I wonder if aerohead has that... Let's see:

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Originally Posted by aerohead View Post
I am university trained in both aerodynamic and hydrodynamic measurement.My senior project (thesis) involved the aerodynamic streamlining of my VW Transporter,which yielded an increase in highway fuel economy,from 27-mpg,to 35-mpg.For nearly 6-years,I earned my daily bread making these measurements.I orchestrated the wind tunnel testing of the Cd 0.11 Becker-Lyon,BMW,LSR motorcycle streamliner.I hold two USFRA speed records.Since 1986,I've probably been part of only a rarified community of motorists incorporating a relative-wind-seeking,slewing pitot-tube/airspeed indicator.
Since my projects mimic vehicles which have already been analyzed by simultaneous recordings of 42-pressure tap/manometer readings,drilling my car full of holes,and bankrupting myself purchasing hardware would be folly.I've been happy enough to spend thousands of $ on 3rd-party testing.
In 1951, Sighard Hoerner reported that the average passenger car had a frontal-area-based coefficient of lift of 0.40.At 50-mph,this translated to 60-pounds lift,on a car of 4,500-pounds.
The 1935 Jaray-Adler Sportwagen was measured at Cl= 0.20,which would generate 30-pounds lift under the same conditions.
Spirit of Ecomodder indicated a Cl= 0.00591.At 135-mph she generated 8-pounds of downforce.For a 4,220-pound vehicle this is essentially a 'zero-lift' vehicle. Modelled in part,after the FKFS K-cars,which FKFS reported as 'neutral',as far as lift is concerned.
There's a reason Hucho wasn't concerned with passenger car lift,as of 1987.Can you imagine why? And can you tell the audience what has changed about Earth's atmosphere,or physics since then,that we should obsess over it now?
I thought something like this about your training was true, but I could not find the references to your training that I remembered from years past, so I stayed silent. Many people here are grateful for your participation in this forum, myself included. Members such as Julian are valued, by me, too. But I want to see more respect and less arrogance, more discussion and encouragement, less belittling and insulting. That is what I have always prefered about this forum and among the things that makes it different and better than most other car forums I have seen.

A lotta smart people here, but we're just people. Thanks.

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Old 05-15-2020, 11:26 AM   #42 (permalink)
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how supposed to work

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Originally Posted by JulianEdgar View Post
Yes, I have always wondered how this was supposed to work. Has anyone ever seen a tech paper on this type of design? It would be really interesting to see some tuft testing.
Their patent explains its operation.
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Old 05-15-2020, 12:23 PM   #43 (permalink)
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Their patent explains its operation.
Why the sudden onset of introversion?
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Old 05-15-2020, 12:43 PM   #44 (permalink)
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introversion

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Why the sudden onset of introversion?
The object is to stay in the rational mind,and limit myself to factual/informational-based dialogue.Logic. Brevity. A bit of a challenge in light of the ad hominem attacks.
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Old 05-15-2020, 12:51 PM   #45 (permalink)
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The object is to stay in the rational mind,and limit myself to factual/informational-based dialogue.Logic. Brevity. A bit of a challenge in light of the ad hominem attacks.
OK, we have different "objects".

Anyone care to share the stated purpose of the mentioned Ford patent as to its purpose?

And I'll share my observations on "ad hominem attacks", there is usually at least a shred of truth involved, and the one throwing the shade seldom gains any points with the audience on the sidelines, but I maybe wrong.
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Old 05-15-2020, 01:06 PM   #46 (permalink)
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The object is to stay in the rational mind,and limit myself to factual/informational-based dialogue.Logic. Brevity. A bit of a challenge in light of the ad hominem attacks.
Excellent. Now work on word spacing. You're already doing much better.
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Old 05-15-2020, 01:07 PM   #47 (permalink)
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share

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Originally Posted by j-c-c View Post
OK, we have different "objects".

Anyone care to share the stated purpose of the mentioned Ford patent as to its purpose?

And I'll share my observations on "ad hominem attacks", there is usually at least a shred of truth involved, and the one throwing the shade seldom gains any points with the audience on the sidelines, but I maybe wrong.
I have the patent at home. It's best to read right from it rather than trust my oxidizing white and gray matter. It will be mid-week,next week before I'm back to town.
A loose explanation: the bi-wing would allow the inviscid flow to strike the wings, thereby allowing some re-attachment on the boot, plus capture a locked-vortex on top of the boot, over which inviscid flow could pass , just as it does on the GM 1/2-tonneau, plus sequester the vortex away from the back of the car, isolating it from the low static pressure. The re-attachment would kill rear lift. Flow over the vortex would allow decelerated flow , which helps increase base pressure (Bernoulli), and reduce pressure drag (Hucho and everybody else). It's not as good as a proper fastback , but it's a lighter car, with great rearward vision. And sold in Germany as the Merkur, it helps keep owners alive on the Autobahn at high speed.
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Last edited by aerohead; 05-15-2020 at 02:13 PM.. Reason: add data
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Old 05-15-2020, 01:33 PM   #48 (permalink)
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I spoke too soon (by one minute). You could go back to #47 and add spaces after each sent[i]ence.
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Old 05-15-2020, 02:09 PM   #49 (permalink)
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spaces

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I spoke too soon (by one minute). You could go back to #47 and add spaces after each sent[i]ence.
Done!
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Old 05-15-2020, 03:38 PM   #50 (permalink)
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