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Old 03-31-06, 05:17 PM   #1
Ducimus
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Default Fuel consumption

Anyway to tell exactly how much fuel we're burning?

Here's what got me thinking:

A bit ago i noticed that when i was recharging batteriess at "ahead slow" the port diseal was at 200 RPMs and the starboard diesal at 500 RPMs. By comparision, Flank speed is 500 RPMs.

So for the 3 or 4 hours your rercharging batteris you have one engine going at flank speed. Or to put it another way, a total of 700 RPMs of fuel burning if at "ahead slow".

Of course this brings up the question, how much of a factor is RPM in fuel consumption and how do the various RPM's scale in consumption? Im guessing either 1 to 1 ratio or exponentially.

If 1 to 1, logic would indicate that say

24 hours of a combined total of 400 RPM (200 each engine) would burn more fuel then 4 hours of 700 RPM (500 on one engine, 200 the other.)

But what if RPM fuel consumption scales exponenitally? that 4 hours of 500RPM + 200 RPM would burn ALOT more fuel then on a 1 to 1 ratio, woudln't it?

Maybe im looking into this too much., :hmm:

Anyone follow what im wondering about here? To me, ingame, fuel consumption is one of my biggest concerns.
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Old 03-31-06, 06:12 PM   #2
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Default Re: Fuel consumption

Quote:
Originally Posted by Ducimus
1. Anyway to tell exactly how much fuel we're burning?

2. Of course this brings up the question, how much of a factor is RPM in fuel consumption and how do the various RPM's scale in consumption? Im guessing either 1 to 1 ratio or exponentially.

1. No. It's an "art".

2. For each engine, there is a most efficient RPM to run, with respect to fuel and power. Generally speaking, this point is somewhere between .66 and .80 of maximum horsepower (for compression engines; i.e. diesel). The scale is definately *never* linear; some engines come closer than others, but you're usually looking at some kind of exponential curve with respect to horsepower/fuel. Although, I'm not completely sure any of this is modeled in-game. It might very well be 1:1. :rotfl: :rotfl:
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Old 03-31-06, 06:50 PM   #3
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something tells me im gonna have to mod the fuel on a boat to a known and easily roundible figure, make several runs at various speed settings over a set time period and do this the hardway.
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Old 03-31-06, 06:55 PM   #4
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My Chief Engineer tells me that I'm out of fuel, but my Navigator tells me I have another 800km - go figure.....
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\"Ein U-boot ohne Sehrohr ist heute angekomman - A U-Boat without a periscope arrived today.\" - Message sent to Gunther Prien in U-47 during the Norwegian Campaign by Karl Doenitz to tell Prien about the birth of his second daughter...
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Old 04-01-06, 12:49 PM   #5
Sailor Steve
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Quote:
Originally Posted by Montbrun
My Chief Engineer tells me that I'm out of fuel, but my Navigator tells me I have another 800km - go figure.....
You didn't say whether the engines are still running or not.
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Old 04-01-06, 01:10 PM   #6
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Quote:
Originally Posted by Ducimus
something tells me im gonna have to mod the fuel on a boat to a known and easily roundible figure, make several runs at various speed settings over a set time period and do this the hardway.
I'm afraid so...
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Old 04-01-06, 02:40 PM   #7
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Quote:
Originally Posted by Sailor Steve
Quote:
Originally Posted by Montbrun
My Chief Engineer tells me that I'm out of fuel, but my Navigator tells me I have another 800km - go figure.....
You didn't say whether the engines are still running or not.
This has happened to me also. I was coming back from the Caribbean
in my IXD2 and both officers gave conflicting messages. It seems the nav officer is the correct one.
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