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Originally Posted by NachtRitter
No, I don't believe I am... the wiki page you linked discusses g as acceleration as well... in order to rise vertically at a steady speed, you will need an upward force that directly counteracts the downward pull of gravity, or, since F = ma, you would need ma = mg and since mass is equal, a = g. I don't know how that is a misuse of the term?
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I don't want to argue that in this thread since it doesn't matter to this subject.
Quote:
Originally Posted by NachtRitter
I would suggest removing the arbitrary flat section (how much of a flat section? what is the total travel time / total travel distance?); this just muddles things. Just focus in on the hill section only, base to crest. There are already more than enough variables in that short section. If you assume the starting and ending speed are the same, which approach is better. Then what if you assume the average speed from bottom of hill to crest is the same (which would mean Method 2 starts out slower), which approach is better. I don't have the answer, but that's how I would constrain it.
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If you remove the flat section, & the total time is not the same then you're answering the question "which is the lowest fuel cost method to get up the hill". This is a good question for a hypermiler & I'd like to know the answer too, & I agree the answer probably won't be constant speed, but my question is more practical. In the real world most of us trade off fuel consumption with time, so fixing the time variable, what is the most fuel efficient way to drive?
The starting and ending speed must be the same or it isn't a relevant test.
There are a lot of inputs, such as the length of the flat section, & the length & grade of the climb, but I don't see a way to eliminate the flat section and have a good comparison.
Quote:
Originally Posted by NachtRitter
From my own perspective, I wouldn't drive differently on the flats just because I *might* choose DWL or choose P&G when I encounter a hill. I would wait until I encounter the hill then choose what I believe to be the best method depending on the size of the hill, the grade, and the current conditions (traffic, etc). Heck, I might even change from "pulse" to DWL in the middle of my climb and then back to "pulse" depending on changing conditions. All of that would be SOP (seat of pants) because I'm sure as heck not going to stop, measure the parameters of the hill, plug them into a formula or script and then use the approach that calculates out to a 0.001% (or whatever) fuel savings.
And with a different car, I would probably do it differently. As they say, YMMV.
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All true, & traffic typically forces the issue anyway. But if you knew what the best solution was for a typical grade wouldn't you at least try it?