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Old 09-29-2015, 10:51 AM   #37 (permalink)
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The fineness ratio and small changes to a basic "Bus shape", are to be respected.

I'm learning something from this topic.

EDIT: found this debatable graphic and claims.

EDIT-2: more....................

Over the years, Cohen and his team have won multiple awards to help fund their efforts. First, Cohen won a $1,000 grant from Ashoka Youth Venture to get his project off the ground. Then in 2010, the team won a $25,000 award from the Pepsi Refresh Project to further research and development.

This year, Cohen is receiving a $36,000 award from the Diller Teen Tikkun Olam Awards for both his research and education. Cohen and his mother, Jakee Cohen, both expressed their gratitude toward the Helen Diller Family Foundation.
I like this comment:
KenC • a year ago
While I applaud the efforts of these young people to promote energy conservation, the claims that a simple fairing added to a school bus could cut overall fuel consumption by 10-20% is an extraordinary one (that claim is made on your show and on their site). Extraordinary, because air drag has little effect at speeds below 40 mph, where most school buses spend most of their time, and the fairing is relatively small.

Tests were done by Georgia Tech on tractor-trailer trucks ( ) with more extensive aerodynamic modifications, and they measured less than 7% fuel efficiency improvements at speeds of 65-75 mph. Since air drag is a square law, only 1/4 the savings would be seen at 35 mph (< 2%).

As Carl Sagan says, extraordinary claims require extraordinary evidence. I would like to see the details of the test conditions and data that lead them to make these claims. Not providing this data on the web site raises concerns. I fear that Greenshields will be a dead end, perhaps these entrepreneurs should invest their personal energy in a more promising area?

I think they would get better use of that shield if they cut it off at the high point, and attached it to the back top edge of the bus.

I like the idea, but Aerohead has answered this same question many times in the forum and said the additional frontal area just doesn't pay off. At least that's what I recall, will stand corrected if my memory is bad.
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Last edited by kach22i; 09-29-2015 at 11:02 AM..
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