Fuel Consumption Calculator

[cuthound]

HP produced is a function of engine revs and fuel used.

If your engine is doing (say) 2000 RPM it will generate exactly the same HP & use the same amount of fuel - It doesn't matter if you are on a tidal river, going with or against the flow or aground in a shallow canal, 2000 rpm is 2000 rpm, will generate the same HP and will be using the same amount of fuel.

 

You may well be going at different speed over the ground (or not moving at all) but your HP & fuel usage is the same.

Notvsure I agree with that, although my experience is with diesels powering standby generators.

 

These were governed to a fixed speed, usually 1500 rpm, and during factory testing we would accurately measure fuel consumption with a fuel flowmeter. Typically fuel consumption would increase by 40% from off load to 100% load.

[Sea Dog]

Edited to remove rubbish. Which was all of it

Edited January 19, 2016 by Sea Dog

[Tony Dunkley]

 

That sounds wildly inaccurate for a BMC 1.5.- that would mean we'd burn 8 to 10 gallons a day which would empty our tank in less than a week...

 

In it's marine engine form, as turned out by Newage/Tempest/Wortham Blake etc, the 1.5 BMC Diesel was governed to a maximum of 3600 rpm at which it can develop 36 bhp on full load. For the engine to be on full load at those rpm's, the propeller must be matched to the engine, and the boat, so that the engine is just able to attain it's governed maximum speed with the boat underway. Running under those conditions the fuel consumption would be in the order of 1.7 gallons/hour, any less than that means the propeller is too 'light' [under-propped], and not capable of absorbing all of the power that the engine can produce.

[mick55]

Beta Marine performance figures are based on an internationally accepted standard, this being a Torque Pull Down Test, there is no recognised international standard of measurement based on propeller law, any figures published based on propeller law are totally theoretical and therefore should be treated as such.

[Alan de Enfield]

Beta Marine performance figures are based on an internationally accepted standard, this being a Torque Pull Down Test, there is no recognised international standard of measurement based on propeller law, any figures published based on propeller law are totally theoretical and therefore should be treated as such.

 

Indeed but without either manufacturers curves or Dyno's all we can do is estimate a theoretical figure,

 

This makes interesting reading

 

http://www.frontierpower.com/library/makingsense.htm

[ditchcrawler]

And non of this will tell you the consumption of your boat

[mick55]

 

Indeed but without either manufacturers curves or Dyno's all we can do is estimate a theoretical figure,

 

This makes interesting reading

 

http://www.frontierpower.com/library/makingsense.htm

You have hit the the nail on the head, it is an estimation to a theoretical figure, torque pull down test is done to an ISO standard so cannot be disputed or misinterpreted, figures for prop based consumption has no recognised ISO standard therefore fuel consumption cannot be calculated.