volvo - 182 gallons per hour?

JEG

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Technical data for my engine shows a graph for fuel consumption - optimum revs. appears to give 182 g/hph [grams per hour?]. Can anyone enlighten me on the meaning of this?

Hopeful thanks

John G
 
g/kwh is metric gramsof diesel per kilowatt hour .

If you want to get back to gallons per hour you need to know

The specific density of diesel in kg per thousand litres which i believe from memory is about 840 kg for 1000 litres .

1 gallon is 4.546 litres.

You should know from your engine fact sheet the number of kw it will produce at a set rpm if it is fully loaded by the propeller ( they dont seem to be) so this tells you how many gramms of diesel are burnt every hour to produce one kw of energy multiply by the total number of kw the engine produces to find the number of gramms of diesel that is .

check but 0.84 i think is the weight in gramms of a litre of diesel ( it varies a little with grade and temerature) so that gives you the total litres your engine will use at any load to produce the set number of kw. Then multiply by two for twin engine boats then divide by 4.546 to get gallons per hour.

All of my boats seem to not use the manufacturers full fuel load .

Dont forget that most people dont usualy run at at max rpm all the time and that ba diesel engine although producing the rpm may not be using the full ammount of diesel as the prop is not absorbing all of the energy to turn at that speed.

In theory if you keep all of your figures religeously enough you can calculate the total KW you actually use per hour generally well below the max.

Do this and bobs your uncle or if you get the decimal point in the wrong place your aunty as the case may be.
 
An Imperial gallon is 4.546 litres.
A US gallon is 3.785 litres.
Still don't know what g/hph is. Could it be grams per horsepower-hour?
One horsepower-hour (US) is 0.7457 kilowatt-hour.
One metric horsepower-hour is 0.7355 kilowatt-hour.
Does this help?
 
Looks like grams per horsepower-hour is the correct notation.
The value of 182 grams fuel per metric horsepower-hour is reasonable for a diesel engine based on Bandits assumption of 840 kg for 1000 litres and assuming metric horsepower.
 
Bandit

I think the other forumites are correct with the grams/horsepower/hour.

If they are, to run your engine for 1 hour would work out as follows:-

182g X 150 hp x1hr = 27300g/hph.

on that basis 27300g = 27.3kilograms. 1 litre of water = 1kg Fuel wont be much different so for rough calcs lets assume they are the same

So 27.3Kg = 27.3litres divide that by 4.54 = roughly 6Gallons/hour which for full load on a 150hp isnt that far away.

Hope this helps and also hope my math is right or I'm going to look a prize plank on the forum! /forums/images/graemlins/smile.gif

Cheers JH
 
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