Perhaps you didn’t explain your intent well enough to begin with.
There is alot of difference when it comes to the "oxygenated fuels introduced in th eWinter months here in NH. When that switch occured, my 2001 Eclipse V6 would drop in mileage from 30 to about 24…very abruptly.
You then go on
…an energy company that is selling energy by the gallon (doesn’t make sense) has much incentive to “volumize” that gallon with the cheapest volumizer
Since measuring by weight does nothing to solve the problem of winter fuel being less efficient, the clear and obvious answer would be to sell it by energy content. Impractical, of course, but that way you’d be getting the energy that you’re paying for. I don’t necessarily agree that they’re “volumizing” gasoline for the sake of making more money though. Higher volatility is required during the winter, and prices tend to decrease during the winter season. Later you say
You will notice naval, railroads, aviation, etc spaek[sic] of fuel weight, not volume.
As I said, I’ve noticed that large scale aviation speaks in terms of fuel weight, but it has nothing to do with a more accurate calculation of energy content, it has everything to do with insuring proper weight and balance. Large naval vessels may have to consider weight to achieve proper buoyancy. I imagine they have weight and balance calculations similar to aircraft based on their configuration and the placement of their cargo. Railroads may have concerns about the weight of each car based on rail restrictions, limits of the running gear, or other restrictions. I’ll bet over the road tanker trucks sometimes speak in terms of weight, since they’re limited to an 80,000 lb total vehicle weight, and diesel fuel and
gasoline have different densities. Your assertion that they do it because it’s a better way of determining actual energy content is incorrect.
However, mass does equalize the advantages of volumetric change due to heat.—nuff said on that.
I never claimed anything to the contrary, did I? But how would you do that at the pump? Drive over a scale before filling up and then again afterward? And remove the trash bins so people can’t be throwing out gallon jugs full of water? Wouldn’t the more practical thing to do be to adjust based on temperature, like they do when the fuel gets delivered to the station? That’s the real solution here. Gasoline is going to continue to have different formulations with different energy contents dictated by seasonal and regional needs, and they will continue to be priced accordingly, with formulations like winter gas and E85 priced lower because of lower energy content. The only practical solution to this problem is to adjust the volume to the standard 60 degrees Fahrenheit.
All that crap is not going to happen but, yes weight difference between prefill and fill is perfect…it works fine, I do that with industrial batch processes in work that I do. However 'll surrender on that because there’s no mystery here…its just chemistry and physics… I wanted to just point out to everyone the issues, though not enormous, caused by using volume… So, if we could only engineer better systems to use tha energy, we’d be better off…We’ve been using the IC recipro…in its present form with no real functional change for nearly 120 years.
I guess those tables are included in the Engine Operators Handbook, not in the normal Pilot’s Operating Handbook that I’m used to seeing. It’s related to “Propeller Power Load.” So it’s related to each aircraft type. It still doesn’t have to do with gasoline though. Like I said earlier, gasoline engines measure fuel consumption in gallons per hour, not pounds. Only a turbo-shaft jet engine driving a propeller would measure by weight. I don’t know if the same kinds of disparity in energy content exists between JET-A as does with gasoline. For that matter, I’m not sure that there are different winter and summer blends of 100LL (avgas).
Folks, I’m a professional in the heat transfer area, and I can’t help weighing in on the narrow question of who buys the drinks. Short answer…it depends. If I were one of the bettors, I would insist on being declared the winner no matter how small the effect, even a fraction of a degree. Now, a few people have correctly pointed out that the tank temperature does not vary much during the day because it is buried. You might claim that, even so, the tank would be slightly colder during the colder part of the day. Not so! There is a time lag to the temperature cycle. The deeper the tank, the greater the lag (and the smaller the temperature variation). So if the tank were very shallow, the time lag would be small, and yes, the tank would be coldest not long after the day is coldest. But if the tank is deep, the tank could even be coldest when the day is hottest. In any event, it makes no measurable difference.
As an analytical chemist, I wanted to chime on the “nitrogen enriched” comment: the author is 100% right that adding gaseous nitrogen (N2) to gasoline would simply be inert. However, the foo-foo dust added to the premium gasoline at a particular station is likely an additive that is a nitrogen-containing organic compound. It is far easier to market “nitrogen enriched” than to bewilder the masses with organic chemistry nomenclature.
Folks, IMHO the arguement is strictly academic. Other factors such as ehen was the tank truck last there, how long was the gas in the truck’s tank, what was the ambient temperature around the truck when the gas was being transported, and even how agitated is the gas (less so in a Lincoln I suspect than in a Tacoma), and even what teh ambient air prssure is…all of these affect the end result as well as and as much as the other variables.
Look, the tank may be in a relatively constant 56 degrees, but if it’s in the sun belt and was just filled by a tanker truck that just traveled 100 miles in 100 degree temperature at 70 mph, what temperature is the gas when pumped? And how long does it take for the gas to drop to 56 degrees? At a station that pumps 10,000 gallons daily, what really is the average temperature in the tank? I think it’s a safe bet that it’s not the same as a station in New England that’s just been filled by a truck that traveled 100 miles in 30 degree weather. How long does it take for that gas to warm to 56 degrees? If the station pumps 10,000 gallons daily, does it ever reach 56 degrees?
I agree that it’s a myth that you should fill up in the morning. There are too many uncontrollable variables for you to affect the final value you get for your dollar.