Abstract:
A fuel system for use in an internal combustion engine includes a plurality of fuel injectors, each injector including at least one capillary flow passage, the at least one capillary flow passage having an inlet end and an outlet end, a heat source arranged along the at least one capillary flow passage, the heat source operable to heat a liquid fuel in the at least one capillary flow passage to a level sufficient to convert at least a portion thereof from the liquid state to a vapor state, and a valve for metering fuel to the internal combustion engine, a controller to control the power supplied to the heat source of each of the plurality of fuel injectors to achieve a predetermined target temperature, a sensor for use in determining engine air flow and a sensor for measuring a value indicative of degree of engine warm-up of the internal combustion engine. According to a further aspect of the present invention, an initial liquid fuel pulse is purged from the fuel injector while the intake valve is in a substantially closed position so as to further minimize hydrocarbon emissions at startup.
Abstract:
A method for controlling a fuel system of an internal combustion engine (810). The method is employed with a fuel system having a source (710) of alcohol-containing liquid fuel, at least one fuel injector (900), a heat source for heating the liquid fuel in the at least one fuel injector (900), the heat source capable of heating the liquid fuel to a level sufficient to convert at least a portion thereof from the liquid state to a vapor state and a metering valve operable to achieve a range of flow rates characterized by a valve open versus valve closed duty cycle. The method includes the steps of metering a predetermined amount of fuel based on engine operating conditions, controlling power supplied to the heat source of the at least one fuel injector (900) to achieve a target temperature, determining alcohol concentration of the fuel and adjusting the power supplied to the heat source of the at least one fuel injector based on the alcohol concentration determination. A method of determining alcohol concentration and a fuel system for use in an alcohol fueled internal combustion engine is also provided.
Abstract:
An apparatus and method for improving the transient response of a spark-ignited fuel-injected internal combustion engine is disclosed. This is accomplished by employing one or more novel capillary fuel injectors (700). These devices are port fuel injectors (700) modified by inserting one or more relatively small diameter heated tubular capillaries (712) between the fuel line and a conventional injector. Sufficient heating can be produced so that flash vaporization occurs as the fuel exits the injector. The heaters are turned on using control algorithms that can be based on exhaust gas oxygen concentration, load on the engine, and accelerator pedal position.
Abstract:
A fuel injector for vaporizing a liquid fuel for use in an internal combustion engine. The fuel injector includes at least one capillary flow passage (12) , the at least one capillary flow passage (12) having an inlet end (14) and an outlet end (16), the capillary flow passage comprises a channel formed within a monolithic body produced from a material selected from the group consisting of ceramics, polymers, metals and composites thereof or a multi-layer ceramic body, a fluid control valve (18) for placing the inlet end of the at least one capillary flow passage (12) in fluid communication with the liquid fuel source and introducing the liquid fuel in a substantially liquid state, a heat source (20) arranged along the at least one capillary flow passage, the heat source (20) operable to heat the liquid fuel in the at least one capillary flow passage (12) to a level sufficient to change at least a portion thereof from the liquid state to a vapor state and deliver a stream of substantially vaporized fuel from the outlet end of the at least one capillary flow passage.
Abstract:
A fuel system for use in an internal combustion engine includes a plurality of fuel injectors, each injector including at least one capillary flow passage, the at least one capillary flow passage having an inlet end and an outlet end, a heat source arranged along the at least one capillary flow passage, the heat source operable to heat a liquid fuel in the at least one capillary flow passage to a level sufficient to convert at least a portion thereof from the liquid state to a vapor state, and a valve for metering fuel to the internal combustion engine, a controller to control the power supplied to the heat source of each of the plurality of fuel injectors to achieve a predetermined target temperature, a sensor for use in determining engine air flow and a sensor for measuring a value indicative of degree of engine warm-up of the internal combustion engine. According to a further aspect of the present invention, an initial liquid fuel pulse is purged from the fuel injector while the intake valve is in a substantially closed position so as to further minimize hydrocarbon emissions at startup.
Abstract:
An internal combustion engine and a method of operating same is provided with direct injection of gaseous fuel into a combustion chamber and an ignition assist apparatus disposed within the combustion chamber. An ignition assist apparatus disposed within the combustion chamber comprises an electric incandescent ignitor with a sleeve disposed around the ignitor and a catalytic alloy. The catalytic alloy comprises a first catalytic element with a greater affinity for oxygen than that of a second catalytic element, and the second catalytic element having a greater affinity for the fuel than that of the first catalytic element.
Abstract:
A fuel injector for vaporizing a liquid fuel for use in an internal combustion engine. The fuel injector includes a plurality of capillary flow passages, each of the plurality of capillary flow passages having an inlet end and an outlet end; a heat source arranged along each of the plurality of capillary flow passages, the heat source operable to heat the liquid fuel in each of the plurality of capillary flow passages to a level sufficient to change at least a portion thereof from the liquid state to a vapor state and deliver a stream of substantially vaporized fuel from each outlet end of the plurality of capillary flow passages; and a valve for metering substantially vaporized fuel to the internal combustion engine, the valve located downstream of each outlet end of the plurality of capillary flow passages. The fuel injector is effective in reducing cold-start and warm-up emissions of an internal combustion engine.
Abstract:
An apparatus and method for improving the transient response of a spark-ignited fuel-injected internal combustion engine is disclosed. This is accomplished by employing one or more novel capillary fuel injectors. These devices are port fuel injectors modified by inserting one or more relatively small diameter heated tubular capillaries between the fuel line and a conventional injector. Sufficient heating can be produced so that flash vaporization occurs as the fuel exits the injector. The heaters are turned on using control algorithms that can be based on exhaust gas oxygen concentration, load on the engine, and accelerator pedal position.