SAE paper on Pulse and Glide

[bwilson4web]

Hi,

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:

• "Prius Technical Stuff"
• MyHybridCar.com

I am not interested in 'trolling for members' to either site but there is the technical issue of trying to address discussions in multiple threads. It is my hope that someone in PriusChat may also buy their copy and look at SAE 2009-01-1322. If there is an interest in technical aspects of this paper, I'll be happy to offer some thoughts.

The short form of my concern is I don't think this 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, are nearly twice the value I've found in my field testing, 11%.

BTW, this paper makes a number of valuable, 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

ps. Moderators, I'm posting this note here instead of either the Technical for Fuel Economy forums because of the unexpected rant that showed up after my earlier evaluation of different mileage databases. Apparently there are 'sacred cows' and a few folks behaved badly around some bovine subjects. <grins>