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Old 04-21-2009, 10:23 AM   #5 (permalink)
Engineering first
bwilson4web's Avatar
Join Date: Mar 2009
Location: Huntsville, AL
Posts: 814

14 i3-REx - '14 BMW i3-REx
Last 3: 45.67 mpg (US)

17 Prime Plus - '17 Toyota Prius Prime Plus
90 day: 58.25 mpg (US)
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Thanked 212 Times in 136 Posts

I've started two threads about SAE 2009-01-1322 to discuss "Vehicle Inertia Impact on Fuel Consumption of Conventional and Hybrid Electric Vehicles Using Acceleration and Coast Driving Strategy" Lee, Nelson, and Lohse-Busch:I am not interested in 'trolling for members' to either site but there is a technical issue of trying to address discussions in multiple threads. It is my hope that someone here may also look at SAE 2009-01-1322 and if there is an interest in technical aspects of the paper, we may explore the paper.

The short form of my concern is I don't think the paper has properly factored in aerodynamic drag. If so, it may go a long way to explaining why their pulse and glide results, 25% better, or nearly twice the value I've found in my testing, 11%.

BTW, I think this paper makes a number of significant and important advances and in particular I appreciate:
  • comparing P&G vs. equivalent constant speed
  • modeling both
There is much more right with this paper and I believe it should be the starting point for follow-up papers that fully address what is going on.

Bob Wilson
2019 Tesla Model 3 Std. Range Plus - 215 mi EV
2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade
Retired engineer, Huntsville, AL
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