[SGVLUG] OT: Hybrid efficiency (was:New Linux Lug)
Tom.Emerson at wbconsultant.com
Tue Feb 21 14:33:41 PST 2006
> -----Original Message-----
> Behalf Of David Lawyer
> Thanks for discussing this with me. I think I'll write an article
> named "The Case for Coasting" and explain this better. I can't just
> say to recover KE by coasting without explaining it in detail.
This sounds like a great "myth" for the Mythbusters to pursue -- recent fuel-effeciency tests have concluded:
-- it is better to use A/C than to roll down the windows, but given the flak on the viewer forum over this, it appears they made some significant mistakes on the testing, and really what they "proved" was that "at over 60 mph, it is better to roll up the window..." yeah, drag and stuff seeps into this one as well.
-- it is better to drive with the tailgate UP in a pickup truck. This was empirically proved by driving identical trucks with a full tank; got about 10 miles further with the tailgate up. Turns out later experiments with a "water tunnel" [same as a wind tunnel, but using water and styo balls instead of "smoke"] showed that the design of the truck is such that the tailgate actually traps a "bubble" of air behind the cab and causes the airflow to goe over the tailgate. With the gate down, the "bubble" deflates and the airflow then impinges upon the last half of the truckbed and tailgate, thus inducing additional drag.
There is also another show by the name of "Brainiac", which is a British-born derivative of Mythbusters, but with no real intent on "proving" anything scientifically [as their tagline states, they are into "science abuse"...] I believe they did a segment of pulse-driving vs. flat-out, and the pulse-driver didn't go as far. I can't find a specific reference to this episode, and I only caught the "conclusion" while channel surfing, so I feel this is somewhat suspect...
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