Optimized fuel management system for direct injection ethanol enhancement of gasoline engines
AssigneeMassachusetts Institute of Technology
InventorsLeslie Bromberg, Daniel R. Cohn, John B. Heywood
Life of this patent
Estimating the term…
Abstract
Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.
Claims21
A fuel management system for spark ignition engine where the fuel management system controls fueling from a first fueling system that directly injects fuel into at least one cylinder as a liquid and increases knock suppression by evaporative cooling and from a second fueling system that injects fuel into a region outside of the cylinder;
- and where there is a range of torque where both fueling systems are used at the same value of manifold pressure;
- and where a fraction of fuel in the cylinder that is introduced by the first fueling system increases with increasing manifold pressure so as to prevent knock by providing increased knock resistance;
- and where the fuel management system controls the change in the fraction of fuel introduced by the first fueling system using closed loop control that utilizes a sensor that detects knock and where open loop control is also used;
- and where the open loop control uses an engine map lookup table;
- and where open loop control is used during transients.
A fuel management system for spark ignition engine where during at least part of the driving time the fuel management system controls fueling from a first fueling system that directly injects fuel into at least one cylinder as a liquid and increases knock suppression by evaporative cooling and from a second fueling system that injects fuel into a region outside of the cylinder;
- and where there is a range of torque where both fueling systems are used at the same value of manifold pressure;
- and where a fraction of fuel in the cylinder that is introduced by the first fueling system increases with increasing manifold pressure so as to prevent knock and where the maximum knock resistance is provided by a combination of fueling from the first and second fueling system;
- and the fuel management system controls the change in the fraction of fuel introduced by the first fueling system using closed loop control that utilizes a sensor that detects knock and where open loop control is also used;
- and where open loop control is used during transients;
- and where during engine start up higher a fraction of fuel is provided by the second fueling system than would ordinarily be used.
A fuel management system for spark ignition engine where during part of the drive cycle the fuel management system controls fueling from a first fueling system that directly injects fuel into at least one cylinder as a liquid and increases knock suppression by evaporative cooling and from a second fueling system that injects fuel into a region outside of the cylinder;
- and where the fuel from the first fueling system is injected so as to provide a non-uniform distribution of fuel in the cylinder;
- and where there is a range of torque where both fueling systems are used at the same value of manifold pressure;
- and where a fraction of fuel in the cylinder that is introduced by the first fueling system increases with increasing manifold pressure so as to prevent knock and where the maximum knock resistance is provided by a combination of fueling from the first and second fueling system;
- and the fuel management system controls the change in the fraction of fuel introduced by the first fueling system using closed loop control that utilizes a sensor that detects knock and where open loop control is also used;
- and where open loop control is used during transients.
A fuel management system for spark ignition engine where the fuel management system controls fueling from a first fueling system that directly injects fuel into at least one cylinder as a liquid and increases knock suppression by evaporative cooling and from a second fueling system that injects fuel into a region outside of the cylinder;
- and where there is a range of torque where both fueling systems are used at the same value of manifold pressure;
- and where a fraction of fuel in the cylinder that is introduced by the first fueling system increases with increasing manifold pressure so as to prevent knock by providing increased knock resistance;
- and where the fuel management system controls the change in the fraction of fuel introduced by the first fueling system using closed loop control that utilizes a sensor that detects knock and where open loop control is also used;
- and where the open loop control uses an engine map lookup table;
- and where open loop control is used during transients;
- and where the direct injection of fuel by the first fueling system is carried out so as to minimize wall wetting.
Dependencies are inferred from the claim text.