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View Full Version : So, how many gallons in a cubic meter?

Try2B Comprehensive
06-10-2010, 10:26 PM

After the news conference, the Department of Interior said in a press release that the scientists who based their calculations on video say the best estimate for oil flow before the riser was cut was between 1.05 million gallons a day and 1.26 million gallons a day. That release mentioned only a cubic meter per second rate from Woods Hole, not a rate that translated into actual amounts.

I don't know what's up with those guys at Woods Hole not releasing rates quantifiable in 'actual amounts'. Still, sometimes I waste time asking stupid questions (kind of like a hobby), and today I wonder how many gallons there are in a cubic meter.

running coach
06-10-2010, 10:29 PM
264.1721

jasg
06-10-2010, 10:33 PM
A cool thing about questions like this is that you can get the answer by typing:

gallons in a cubic meter

into the google search screen and it tells you immediately.

pulykamell
06-10-2010, 10:34 PM
Also, if you want to do any kind of unit conversions, Google will do that for you. Just type in "1 cubic meter in US gallons" (or any other amount or units.) For example, "1.26 million gallons in cubic meters" will give you the answer: "1.26 million US gallons = 4 769.61885 cubic meters."

edit: Beaten to the punch.

Try2B Comprehensive
06-10-2010, 11:51 PM
Yeah, but is that an 'actual amount'?

pulykamell
06-11-2010, 12:34 AM
Yeah, but is that an 'actual amount'?

What do you mean by "actual amount"? I see the quote you've posted, but I have no idea what the article means by "actual amount" in that context. 264 gallons is 1 cubic meter. I don't see what's not "actual" about that.

GameHat
06-11-2010, 12:36 AM
Yeah, but is that an 'actual amount'?

Yes, gallons in a cubic meter is a perfectly defined number.

The uncertainty comes in when the DOI (or whoever) tries to convert a rough estimate (Uh...maybe a m^3/s?) into a different unit (uh...maybe 1.05 to 1.26 gal a day?)

pulykamell
06-11-2010, 12:36 AM

1 ((cubic meter) per second) = 22 824 465.3 US gallons per day

So I don't know how 1 cubic meter per second becomes an estimate of about one to one and a quarter million gallons a day.

septimus
06-11-2010, 12:45 AM
A cool thing about questions like this is that you can get the answer by typing:

gallons in a cubic meter

into the google search screen and it tells you immediately.

At the risk of sounding overly pedantic, there are three different gallons and the Google calculater seems to silently assume you want U.S. liquid gallons.

Since this is British Petroleum one wonders if they make quantities seem smaller by quoting in Imperial gallons which are 20% larger than U.S. liquid gallons.

Finally, one may sometimes encounter the U.S. dry gallon, 1/8 of a bushel (though the U.S. bushel is slightly smaller tha an Imperial bushel).

Just saying.

Malacandra
06-11-2010, 01:00 AM
For Imperial gallons you can get a good estimate in your head:
One cubic metre of fresh water = 1 tonne
One tonne = 1 Imperial ton (approx) = 2240 lb
One Imperial gallon of fresh water = 10 lb (definition)
==> one cubic metre = 224 gallons approx.

If you want to get closer you can even start looking things up.

pulykamell
06-11-2010, 01:00 AM

I don't know what's up with those guys at Woods Hole not releasing rates quantifiable in 'actual amounts'. Still, sometimes I waste time asking stupid questions (kind of like a hobby), and today I wonder how many gallons there are in a cubic meter.

Ah, wait, I think I understand this now.

The article is not saying the oil is gushing out at a rate of one cubic meter per second. It's saying that the release by the Department of the Interior gave a rate expressed in cubic meters per second, whose amount apparently converts to 1.05 million - 1.26 million US gallons per day.

So, this amount is a rate, not an actual amount. It's telling you how much and how fast the oil is gushing out, but not giving you an actual number of how much oil over time has gushed out. You need to figure out how long it's been gushing out at that rate to find out the actual amount of oil spilled.

Or so I interpret that paragraph.

septimus
06-11-2010, 04:51 AM
Imperial gallons which are 20% larger than U.S. liquid gallons.

Oops. :smack: I meant that the U.S. gallon was 20% smaller. :cool:

BTW, has anyone here ever had to convert a survey foot to International inches ? :eek:

06-11-2010, 07:09 AM
Grraah.

That is all.

muldoonthief
06-11-2010, 08:47 AM
Ah, wait, I think I understand this now.

The article is not saying the oil is gushing out at a rate of one cubic meter per second. It's saying that the release by the Department of the Interior gave a rate expressed in cubic meters per second, whose amount apparently converts to 1.05 million - 1.26 million US gallons per day.

So, this amount is a rate, not an actual amount. It's telling you how much and how fast the oil is gushing out, but not giving you an actual number of how much oil over time has gushed out. You need to figure out how long it's been gushing out at that rate to find out the actual amount of oil spilled.

Or so I interpret that paragraph.

Yes, converting from cubic meters/second to gallons per day is an excellent 6th grade math problem. Apparently none of those reporters passed 6th grade math, or have 6th graders at home. Of course, the article also has ridiculous but beloved journalistic comparisons like:

If those 63 million gallons of oil were put in gallon milk jugs, they would line up side by side for nearly 5,500 miles. That's the distance from the spill to London, where BP is headquartered, and then continuing on to Rome.

What if you put the oil in juice boxes, and laid them end to end? Then they would reach almost 1/3 of the way to the moon!

regginbrow
06-11-2010, 09:58 AM
The actual amount per day also depends on the actual rate. If the oil is coming out at a constant rate, then this is a simple unit conversion. However, if the oil isn't coming out at a constant cubic meter per second, but actually at a varying rate whose variation is difficult or impossible to determine, this also complicates calculating the 'actual' amount of oil coming out per day.

jasg
06-11-2010, 10:21 AM
Oops. :smack: I meant that the U.S. gallon was 20% smaller. :cool:

BTW, has anyone here ever had to convert a survey foot to International inches ? :eek:... or the Kessel run to sideral days?

pulykamell
06-11-2010, 11:25 AM

Woods Hole Oceanographic’s initial total flow rate estimate of 0.12m3/s to 0.23m3/s from before the riser was cut is a preliminary bulk flow estimate.

That converts to a range of 2,738,935.84 US gallons per day to 5,249,627.02 US gallons per day. So I'm still not sure where the 1.05 million to 1.26 million number comes from. It does also say:

This outflow may contain gases, liquids, and solids including natural gas, condensates, oil, sediments, and produced water.

So perhaps there's an adjustment downward to account for this, but I can't find any solid numbers, just this statement in Woods Hole PDF link on that web page:

A comprehensive understanding of the source composition (e.g., percentage gas, oil, sediment, brine) is needed to
accurately estimate the petroleum leak rate and mass balance.

So, I have no idea where those numbers are coming from.

Chronos
06-11-2010, 12:58 PM
... or the Kessel run to sideral days? Here you go (http://www.google.com/#hl=en&source=hp&q=12+parsecs+%2F+c+in+sidereal+days&aq=f&aqi=&aql=&oq=&gs_rfai=&fp=19d13023017841d)

jasg
06-11-2010, 03:57 PM
Here you go (http://www.google.com/#hl=en&source=hp&q=12+parsecs+%2F+c+in+sidereal+days&aq=f&aqi=&aql=&oq=&gs_rfai=&fp=19d13023017841d)Well, yeah if you include that 'c' fudge factor....but did Han and Chewie stay right at 1 light all the way? ;)

Try2B Comprehensive
06-11-2010, 10:38 PM
What if you put the oil in juice boxes, and laid them end to end? Then they would reach almost 1/3 of the way to the moon!

I doubt juice boxes is an 'actual amount'. It has to be gallons; therefore Rome is okay. Or barrels. Just piling up in London. But not the moon

Try2B Comprehensive
06-12-2010, 05:41 PM
Anyway. Thanks guys, the answer is more interesting than I thought.

06-14-2010, 08:24 AM
Since this is British Petroleum one wonders if they make quantities seem smaller by quoting in Imperial gallons which are 20% larger than U.S. liquid gallons.

Just saying.

Nitpick - No, it is not British Petroleum. The name was officially changed several years ago to simply BP, which is currently the global brand. The company actually expands that out into Beyond Petroleum for marketing, but the actual global brand is only BP.

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