Patent ID: 11959434
Assignee: CLEARFLAME ENGINES, INC.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  Y | IPC F

Claim 45:
46. A method of operating a compression ignition engine, the compression ignition engine including an engine cylinder having an inner surface, a head surface, a piston disposed and configured to move in the engine cylinder, an intake valve, and an exhaust valve, the inner surface of the engine cylinder, the piston, the head surface, the intake valve, and the exhaust valve defining a combustion chamber, the method comprising the steps of:
opening the intake valve to draw a first volume of air into the combustion chamber, the volume of air having a temperature between about 80° C. and about 150° C. while being drawn into the combustion chamber;
closing the intake valve;
moving the piston from a bottom-dead-center (BDC) position to a top-dead-center (TDC) position in the combustion chamber at a compression ratio of at least about 15;
injecting a volume of a first fuel into the combustion chamber at a first engine crank angle during a first time period into air having a first temperature, the first temperature measured at 10 crank angle degrees prior to injecting the volume of the first fuel into the combustion chamber, the first fuel having a first cetane number less than about 40;
combusting the volume of the first fuel;
opening the intake to draw a second volume of air into the combustion chamber; moving the piston from BDC to TDC in the combustion chamber at a compression ratio of at least about 15;
injecting a volume of a second fuel into the combustion chamber during a second time period into air having a second temperature higher than the first temperature, the second temperature measured at 10 crank angle degrees prior to injecting the volume of the second fuel into the combustion chamber, the second fuel different than the first fuel and having a second cetane number lower than the first cetane number;
closing the intake valve; and
combusting the volume of the second fuel, wherein a delay between initiation of injection of the volume of the first fuel and the second fuel into the combustion chamber and initiation of combustion of each fuel is less than about 1 ms.