specific fuel consumption conversion
 

having a bit of dumb moment, can anyone help me convert 0.635 lb/hp-hr to metric units i.e. kg/w-s

many thanks, brain is not at its best today lol

Not in the businness but as an automotive design engineer I find the following a good site Online Conversion - Convert just about anything to anything else

Since horsepower is an ambiguous unit, i.e. there are multiple definitions of what one horsepower is, an exact conversion would require some additional information on what type of horsepower is meant here.

Incidentally, my favourite reference for anything that involves unit conversions is this:

U.S. Department of Commerce - National Institute of Standards and Technology, Guide for the Use of the International System of Units (SI), edition 2008

the horsepower is the shaft horsepower as quoted by rolls royce for a turboprop engine

http://www.rolls-royce.com/Images/mo...cm92-14681.pdf

pounds per hour per horsepower x kilograms/pound ÷ watts/horsepower = kilograms per hour per watt

kg/lb = 0.454
W/hp = 746

so lb/hr/hp ÷ 1643 = kg/hr/W

divide the answer by 3600 for kg/s/W, but you probably don't want to do that. :O

From documentation I have: (Relating to a particular turbo diesel piston engine and nothing to do with aircraft)

Specific Fuel Consumption

0.372 lb/hph or 229 g/kWh (at 2500 rpm)

By extrapolation,

0.635 lb/hph = 391 g/kWh

Hope that helps :8