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Old 10-17-2020, 01:48 PM   #41 (permalink)
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The problem is that the supposedly technical discussion became personal. All people are fragile.

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"People are fragile things, you should know by now
Be careful what you put them through"

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Old 10-17-2020, 04:16 PM   #42 (permalink)
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The statement is non-controversial. Troll harder?

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Editors- Munich
What is the referent?
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Old 10-17-2020, 06:11 PM   #43 (permalink)
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Quote:
Originally Posted by freebeard View Post
The statement is non-controversial. Troll harder?



What is the referent?
That's a band and song.
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Old 10-17-2020, 07:42 PM   #44 (permalink)
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Quote:
Originally Posted by AeroMcAeroFace View Post
MetroMPG, have you considered removing the template from the website seeing as it is so controversial or would removing it be too controversial?
Say what you want negatively about the template, but there have been many modifications built to follow it that have worked. I have done three myself, and got within 1% of the gains I had estimated. (5% half bedcover, 10% full bedcover, 5% kamm shell)

Could I have built something slightly better? Maybe... but what I did worked. So for my fourth big rear tapering modification, I am once again using it as my guide. If my fourth project doesn't deliver as I expect when I test it, I may alter my views but until then 3 for 3 isn't bad. I am always open to other suggestions for tapering patterns.

In fact, there are many examples of these sorts of "template modifications" documented in Julian's book. In fact, page 170 has a full page devoted to a T100 with a full bedcover and a tail... I wonder who built that one...I wonder who picked it as worthy for publication...
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Old 10-17-2020, 08:21 PM   #45 (permalink)
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Needs a smiley face:

People got obsessive about that (actually three) side view. Example from 2018:



Quote:
When I was reviewing some of the equations I've posted I noticed some anomalies with the Angles Rate of change from segment to segment, this would be the acceleration of inclination. Even though the curve itself may look ok, when you chart the rate of change it shows an irregular pattern, just like a hill may appear to have a smooth contour from a distance but is full of ups & downs when you walk it. ... Just as an example I charted some of the original template angles
Schlorwagen is an instantiation. I have my own [un-built] octahedral geodesic aeroform.

One benefit of the Template is giving enough hope to dive in. JethroBodine in 2011 for example, even though he fell wide of the mark.

I think one of the highest uses would be to increase the tumblehome of the top to conform to the front view. Plus blisters and canopies and rooftop air conditioners.
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Old 10-17-2020, 08:27 PM   #46 (permalink)
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Quote:
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In fact, there are many examples of these sorts of "template modifications" documented in Julian's book. In fact, page 170 has a full page devoted to a T100 with a full bedcover and a tail... I wonder who built that one...I wonder who picked it as worthy for publication...
The issue--what I think Julian was arguing, without putting words in his mouth--is that while the template is a low-drag shape, it is often referred to here as the ideal shape. But once you start reading the literature out there, it becomes abundantly clear that there is no one ideal low-drag shape. As RH Barnard puts it in his book Road Vehicle Aerodynamic Design:

Quote:
The teardrop shape in full, half, or modified form has never proved to be the basis for a good practical vehicle shape for everyday use, and as will be shown in later chapters, satisfactory low-drag shapes can be produced without resorting to impractical 'ideal' configurations. The essence of the art of streamlining is simply to devise a geometry that does not produce strongly adverse pressure gradients or a wide wake.
Additionally, a thread I posted here several days ago has another excerpt from this author discussing "ideal" shapes in more detail.

Hucho devotes several pages to discussing "ideal" shapes as well, in the 4th edition of Aerodynamics of Road Vehicles, pp. 212-213 and 224-229. It's worth looking at if you have the book.
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Old 10-17-2020, 08:40 PM   #47 (permalink)
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The elephant hiding in the middle of the room is use case. A vehicle design to any end other than high efficiency at low speeds with require accommodations to a greater or lesser extent.

In this case 'ideal' is a local maxima.

edit: Here's an example of an AI optimized use car — Supercar


A.I. Designed this Car

Were this a three passenger/center drive car, I'd call it a worthy successor to the Volkhart-Saggita V2, which was really hard-pressed as a 4-passenger vehicle.
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Old 10-17-2020, 09:25 PM   #48 (permalink)
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How about we discuss it further in a new thread?

https://ecomodder.com/forum/showthre...tml#post633952
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Old 10-17-2020, 09:56 PM   #49 (permalink)
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Given the general size and shape of the interior of a generic car, the template seems to be a very predictable way of cleaning up the rear end. On any particular car you can get better results, but offering a template is much more constructive than shrugging and telling modders they're on their own and should simply design and test their own prototypes.

While citing a T-100 built to the template is nice, more relevant here is JulianEdgar's false horror at the Insight not meeting the template- and then his addition of a spoiler to his own Insight. Which seems to have brought it closer to the template...

What would be more valuable would be an explanation of how he arrived at that spoiler. What shorter or longer versions didn't do as well? Higher? Lower? How about a good profile pic to put against the template? Simply attacking the Holy Template while seeming to apply it isn't a good method, especially if your position is one of data and testing. Presumably the testing that went into that (beautifully done) spoiler had one experimental version that met the template, or perhaps the final version does. Either one of those facts would have been a much more constructive argument than the ones we got.
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Transmission type Efficiency
Manual neutral engine off.100% @MPG <----- Fun Fact.
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Old 10-18-2020, 12:58 AM   #50 (permalink)
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Here's my related concern. How does one critique and question the legitimacy of technical claims made when we don't know how the person will take it? Even if I'm careful, someone else might not be careful. So, I haven't brought these kinds of things up.


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