Drag factor is a load of crap.

It's drag in terms of force required to propel a vehicle at a given
speed that's important.

The drag factor is derived from that force and a reference area.
Inconsistencies in the way that area is calculated for road vehicles,
makes drag factor mostly a marketing figure.

For vehicles it's frontal area that's used (gross or net?), but wing
profiles generally use plan or surface (wetted) area.

On 17 October 2017 at 16:18, ROBERT via EV <ev@lists.evdl.org> wrote:
> I think the EV1 had a drag coefficient of 0.19.  Does not make the CD = 0.24 
> for a Prius build in 2016 look very good.
>
>
> ________________________________
> From: EV <ev-boun...@lists.evdl.org> on behalf of brucedp5 via EV 
> <ev@lists.evdl.org>
> Sent: Tuesday, October 17, 2017 3:59 AM
> To: ev@lists.evdl.org
> Cc: brucedp5
> Subject: [EVDL] EVLN: EV Question #19: why do electric vehicles have to look 
> so ... silly?
>
>
>
> https://www.stuff.co.nz/motoring/97760520/car-question-19-why-do-electric-vehicles-have-to-look-so-silly
> Car Question #19: why do electric vehicles have to look so 
> ...<https://www.stuff.co.nz/motoring/97760520/car-question-19-why-do-electric-vehicles-have-to-look-so-silly>
> www.stuff.co.nz
> OPINION: If you're ambivalent about electric vehicles (EVs), odds-on it's 
> down to one of two things: range anxiety or the fact they always seem to look 
> a bit silly ...
>
>
> Car Question #19: why do electric vehicles have to look so silly?
> October 12 2017  DAVID LINKLATER
>
> [images
> https://resources.stuff.co.nz/content/dam/images/1/m/7/f/e/u/image.related.StuffLandscapeSixteenByNine.620x349.1m7ci0.png/1507768530182.jpg
>
> [https://resources.stuff.co.nz/content/dam/images/1/m/7/f/e/u/image.related.StuffLandscapeSixteenByNine.620x349.1m7ci0.png/1507768530182.jpg]
>
> You know Nissan Leaf is an EV because it looks silly. But it's less
> aerodynamic than a Mazda3 or Toyota Corolla
>
> https://resources.stuff.co.nz/content/dam/images/1/m/7/f/e/t/image.related.StuffLandscapeSixteenByNine.620x349.1m7ci0.png/1507768530182.jpg
>
> [https://resources.stuff.co.nz/content/dam/images/1/m/7/f/e/t/image.related.StuffLandscapeSixteenByNine.620x349.1m7ci0.png/1507768530182.jpg]
>
> Expect future pure-EVs to look no different to conventional cars. VW is
> doing it already with the e-Golf
> ]
>
> [image]  Toyota Prius popularised the Kamm-tail body shape for eco-cars:
> smooth lines, chopped-off tail.
>
> OPINION: If you're ambivalent about electric vehicles (EVs), odds-on it's
> down to one of two things: range anxiety or the fact they always seem to
> look a bit silly. Or perhaps both.
>
> To many, electric vehicles are a turn-off because they lack a certain visual
> dignity. But are there good reasons for EVs to look like transportation pods
> from the planet Smorth?
>
> Yes, of course. But not all are entirely scientific.
>
> The most obvious one is aerodynamic efficiency. EVs are all about extracting
> the maximum distance from the limited battery power available, so it makes
> complete sense to have a slippery body shape.
>
> Aerodynamics really ony became a thing for cars in the 1930s, and the work
> of German brainbox Wunibald Kamm from that era is still very influential
> today.
>
> The so-called "Kamm tail" combines long, smooth body contours with an
> abruptly cut-off tail. The best-known Kamm-tail car is also one of the most
> recognisable production-car shapes of modern times: the Toyota Prius. Which
> did not start out as an EV, but its electrified hybrid technology did help
> send the automotive industry down that path two decades ago.
>
> That's why so many eco-friendly cars have looked so much like the Prius over
> the years. It's a very clean profile.
>
> Automotive aerodynamics are generally measured by something called drag
> coefficient, represented by a "Cd" number. As a point of reference, a modern
> family car might be in the 0.30-0.35 range. Something quite brick-like, such
> as a Ford Territory SUV, is more like 0.38.
>
> The latest Prius is considered extremely smooth for a series-production car,
> with a figure of 0.24. Even the previous (taxi, anybody?) model was 0.25.
> The new Hyundai Ioniq EV, which looks very Prius-like, is also 0.24. These
> are very impressive numbers.
>
> Simple, really. A silly shape equals smooth windflow. End of story? Not
> quite.
>
> The thing about the Prius and its ilk looking so idiosyncratic is that silly
> body shapes have become synonymous with cutting-edge eco-automobiles, which
> has in turn made them handy marketing tools for makers of EVs. While weird
> styling might turn off the EV-undecided, it'll certainly attract the early
> adopters who want to make a statement.
>
> So while many plug-in hybrid EVs are simply standard cars with extra
> batteries and a socket (think Mitsubishi Outlander PHEV), the trend for
> pure-EVs that run solely on battery power has been standalone/super-weird
> styling.
>
> The Nissan Leaf is perhaps the prime example. It looks extremely silly but
> it's only moderately slippery by modern standards, with a Cd of 0.28. That's
> still really good, but also inferior to a Mazda3 hatchback (0.26),
> Mercedes-Benz C-class (which actually equals the eco-champs with a figure of
> 0.24) or Audi A4, which achieves a remarkable 0.23.
>
> Or consider the BMW i3 EV, which is super-strange looking but only manages a
> Cd of 0.29.
>
> Indeed, modern aerodynamic design allows carmakers to produce very slippery
> shapes that are still quite classic and elegant. Tesla's Model S sedan is
> 0.24 and the forthcoming Model 3 is claimed to achieve 0.23 (the original
> goal was 0.21, which would have been astonishing). Even the next-generation
> Leaf looks a lot more sporty and conventional than the current model.
>
> As EV technology becomes more mainstream and carmakers start to design new
> generations of cars to suit a variety of powertrain options, expect
> pure-electric cars to become less silly looking. Or at least a lot less
> self-conscious.
>
> The humble Volkswagen Golf has a Cd of just 0.27 even in standard form.
> Little wonder that the just-launched e-Golf, which is a pure-electric model,
> uses exactly the same body shape.
> [© 2017 Fairfax New Zealand]
>
>
>
> https://electrek.co/2017/10/11/weird-ev-turns-humans-into-self-driving-cars/
> [https://electrek.files.wordpress.com/2017/10/17c820_02.jpg?quality=82&strip=all&w=250&h=140]<https://electrek.co/2017/10/11/weird-ev-turns-humans-into-self-driving-cars/>
>
> A weird new EV platform ‘turns humans into self-driving 
> ...<https://electrek.co/2017/10/11/weird-ev-turns-humans-into-self-driving-cars/>
> electrek.co
> Self-driving cars face a broad acceptance problem. People are used to cars 
> always having been driven by humans, which has been the case for over a 
> century, and some ...
>
>
> A weird new EV platform ‘turns humans into self-driving cars’
> 2017/10/11  I’m aware that the headline is pretty much an oxymoron and it
> looks like the stupidest thing from the picture above, but please bear with
> me for a second …
> https://electrek.files.wordpress.com/2017/10/17c820_02.jpg?quality=82&strip=all&w=1024
>
>
>
>
> For EVLN EV-newswire posts use:
> http://evdl.org/evln/
> EVDL EV News Archive - Electric Vehicle Discussion List<http://evdl.org/evln/>
> evdl.org
> EVLN - EV News Archive Edited by Bruce {EVangel} Parmenter: EVLN: home | help 
> | archive | news | privacy policy | terms of service
>
>
>
>
> {brucedp.neocities.org}
>
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