Controlled temperature combustion engine
AssigneeThe United States of America as represented by the Administrator of the Environmental Protection Agency
InventorCharles L. Gray, Jr.
Life of this patent
Estimating the term…
Abstract
A method of operating an internal combustion engine wherein intake ambient air is boosted to a higher pressure by passage through at least one compressor and then introduced into the internal combustion engine. Fuel is also introduced into the internal combustion engine for providing combustion in admixture with the air charge at a combustion temperature approximating a target value. Various engine operating parameters, inclusive of torque demand, e.g., accelerator pedal depression, are sensed and the boosted pressure is changed in a manner proportional to a change in the sensed torque demand so as to maintain the combustion temperature at approximately the target value, i.e., below 2100° K.
Claims28
A method of operating an internal combustion engine comprising:
- intaking ambient air through at least one compressor to provide a charge-air at a boosted pressure and introducing the charge-air to the internal combustion engine;
- introducing fuel into the internal combustion engine for combustion in admixture with the charge-air at a combustion temperature approximating a target combustion temperature, and producing an exhaust gas;
- sensing engine operating conditions inclusive of torque demand;
- and
- changing the boosted pressure proportional to a change in the sensed torque demand so as to maintain the combustion temperature at approximately the target combustion temperature, said target combustion temperature being below 2100° K.
A method of operating an internal combustion engine comprising:
- intaking ambient air through at least one compressor to provide a charge-air at a boosted pressure and introducing the boosted charge-air to the internal combustion engine;
- introducing fuel into the internal combustion engine for combustion in admixture with the charge-air, producing an exhaust gas;
- sensing torque demand;
- and
- changing the boosted pressure proportional to a change in the sensed torque demand so as to maintain an approximately constant ratio Hc/cvM wherein Hc is the heat of combustion, cv is the specific heat capacity of the admixture of charge-air, and M is the mass of the charge-air.
A method of operating an internal combustion engine comprising:
- intaking ambient air to provide a charge-air and introducing the charge-air to the internal combustion engine;
- introducing fuel into the internal combustion engine for combustion in admixture with the charge-air at a combustion temperature approximating a target combustion temperature, and producing an exhaust gas;
- passing a first portion of the charge-air through a heat exchanger for heat exchange and by-passing a second portion of the charge-air through a by-pass line around said heat exchanger;
- sensing intake temperature of the charge-air downstream of the by-pass line and the heat exchanger;
- determining oxygen concentration in the admixture;
- sensing engine operating conditions inclusive of torque demand, crank angle and combustion pressure;
- and
- determining a target crank angle for peak combustion pressure at the sensed torque demand;
- bringing the sensed crank angle, into conformance with the target crank angle by controlling the amount of said second portion by-passing the heat exchanger by operation of a control valve in the by-pass line to adjust the sensed intake temperature and/or by regulating the portion of exhaust recirculated.
A method of operating an internal combustion engine comprising:
- introducing a gasoline fuel and charge-air into the internal combustion engine for combustion with a compression ratio of at least 12:1, at a combustion temperature approximating a target combustion temperature, and producing an exhaust gas;
- recirculating a portion of the exhaust gas for admixture with the charge-air and fuel;
- determining peak cylinder pressure;
- determining oxygen concentration in the admixture;
- and
- regulating the portion of exhaust gas recirculated to produce auto-ignition and the peak cylinder pressure within a predetermined location in a combustion cycle.
A method of operating an internal combustion engine comprising:
- introducing a fuel having an octane rating of at least 90 and charge-air into the internal combustion engine for combustion in admixture with a compression ratio of 15:1, to 20:1 at a target combustion temperature predetermined to minimize NOx formation, and producing an exhaust gas;
- recirculating a portion of the exhaust gas for admixture with the charge-air and fuel;
- determining peak cylinder pressure;
- determining oxygen concentration in the admixture;
- igniting the admixture, at a predetermined timing, with a spark from a spark device;
- and
- regulating that portion of exhaust gas recirculated to regulate the final compression temperature and to avoid auto-ignition.
Dependencies are inferred from the claim text.