Quote:
Originally Posted by bikenfool
Minor nit: you are misusing the term acceleration, "In physics, acceleration is the rate at which the velocity of a body changes with time" https://en.wikipedia.org/wiki/Acceleration. Of course, you are correct the engine doesn't know the difference. |
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?
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.
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.