Patent ID: 6966309

Claim:
A method for discharging exhaust gases representative of stoichiometric combustion from the combustion chamber of a lean-burn combustion reciprocating engine, comprising: introducing initial amounts of air and fuel into the combustion chamber of said lean-burn combustion reciprocating engine, said initial amount of air being greater than the amount of air consumed in the combustion of said initial amount of fuel; providing a primary combustion cycle in which said initial amounts of air and fuel are compressed and ignited; determining the excess amount of air not consumed in the primary combustion cycle; confining the products of combustion of said primary combustion cycle within said combustion chamber during at least one subsequent expansion and compression stroke of said engine in response to determining that an excess amount of air remains in the products of combustion after the combustion of said initial amounts of air and fuel; introducing an additional amount of fuel during at least one subsequent combustion cycle, igniting said determined excess amount of air and said additional amount of fuel during said at least one subsequent combustion cycle; continuously confining the combustion products of said primary and said subsequent combustion cycles within said combustion chamber until substantially all of the initial amount of air introduced into said combustion chamber is consumed and the products of combustion confined within said combustion chamber are characteristic of products of stoichiometric combustion; and discharging said products characteristic of stoichiometric combustion from said combustion chamber.