| 摘要 |
A flexible-fuel internal combustion engine apparatus comprises a combustion chamber, an intake valve, a first fuel injector, a second fuel injector, and a computer. The intake valve is operable to admit an intake charge into the combustion chamber. The first fuel injector injects a gaseous fuel directly into the combustion chamber. The second fuel injector injects a liquid fuel into the intake charge upstream of the intake valve. The computer is operatively connected with the first fuel injector and the second fuel injector to actuate injection of fuel respectively therefrom. The computer is programmed to command a gaseous-to-liquid fuel ratio as a function of at least one operating parameter from a group comprising gaseous fuel pressure, gaseous fuel mass, engine speed, engine torque, inlet air temperature, inlet air humidity, knock detection, operating history, torque command, and emissions. |
| 主权项 |
1. An apparatus for delivering two fuels to a combustion chamber of an internal combustion engine, the apparatus comprising:
(a) a first fuel system comprising a first fuel supply and a first fuel pressure regulator operatively connected with said first fuel supply, said first fuel supply comprising a source of a gaseous fuel; (b) a first fuel injector for directly injecting said gaseous fuel into said combustion chamber, said first fuel injector operatively connected with said first fuel pressure regulator; (c) a second fuel system comprising a second fuel supply, a fuel pump operatively connected with said second fuel supply and a second fuel pressure regulator operatively connected with said fuel pump, said second fuel supply comprising a source of a liquid fuel; (d) a second fuel injector for injecting said liquid fuel upstream of an intake valve operative to admit an intake charge into said combustion chamber, said second fuel injector operatively connected with said second fuel pressure regulator; and (e) a computer operatively connected with said first fuel injector and said second fuel injector to actuate injection of fuel respectively therefrom, said computer programmed to:
(i) command a gaseous-to-liquid fuel ratio as a function of inputs comprising at least one of gaseous fuel storage pressure, gaseous fuel injection pressure, gaseous fuel mass, engine speed, engine torque, inlet air temperature, inlet air humidity, intake air manifold pressure, intake air mass, knock detection, operating history, torque command, and emissions;(ii) select a gaseous-fuel operating mode when a quantity of gaseous fuel is above an upper threshold and a liquid-fuel operating mode when the quantity of gaseous fuel is below the upper threshold;(iii) selectively actuate the first fuel injector to inject the gaseous fuel during the gaseous-fuel operating mode, the gaseous-to-liquid fuel ratio being mathematically undefined during the gaseous-fuel operating mode; and(iv) selectively actuate the second fuel injector to inject the liquid fuel during the liquid-fuel operating mode, the gaseous-to-liquid fuel ratio being zero during the liquid-fuel operating mode. |
