A theoretical minimum amount of oxygen is needed to react with the combustible elements (mainly carbon and hydrogen) in a given quantity and type of fuel. In practice an additional (or excess) quantity of air is required to ensure adequate contact between fuel and oxygen to guarantee efficient combustion. There are no hard-and-fast rules defining […]
Locomotive Exhausts Page Under Development This page is still “under development”. Please contact Chris Newman at webmaster@advanced-steam.org if you would like to help by contributing text to this or any other page.’ Background A steam locomotive’s exhaust system is perhaps the most innovative of all the ideas that underpin the “Stephensonian” concept. It’s cleverness derives […]
Primary and Secondary Combustion Air and Combustion Gases Combustion Air is the air drawn through the firebox by the draughting system which allows combustion to take place. Only the oxygen content of the air (approx 18%) is used in the combustion process, the remainder (mostly nitrogen) being inert and serving no function other than wasting […]
The Front-End Limit As discussed on the Grate Limit page, the grate limit occurs when any increase in the rate of fuel delivery produces no increase in evaporation. In other words it represents the maximum rate of heat emission that a firebox can deliver beyond which point any additional fuel added to the firebox produces […]
The Grate Limit as it relates to Boiler Efficiency On page 78 of his book The Red Devil and Other Tales from the Age of Steam, Dave Wardale defines the Grate Limit for a (normal) locomotive firebox as follows: The grate limit is the point “at which even by firing more coal and supplying more […]