Abstract: In certain embodiments, a time-varying spark current ignition system can be applied to improve spark plug ignitability performance and durability as compared to conventional spark ignition systems. Two performance parameters of interest are spark plug life (durability) and spark plug ignitability. In certain embodiments, spark plug life can be extended by applying a spark current amplitude as low as possible without causing quenching of the flame kernel while it is traveling within an electrode gap and/or by applying spark current of a long enough duration to allow the spark/flame kernel to clear a spark plug gap. In certain embodiments, ignitability can be improved by applying a high enough spark current amplitude to sustain the flame kernel once outside the spark plug gap and/or by applying a spark current for long enough to sustain the flame kernel once outside the spark plug gap.

Abstract: In certain embodiments, a unique method and pre-combustion chamber (PCC) structure may ensure very efficient flame propagation of lean fuel-air mixture in natural gas engines by reducing the amount of fuel admitted to the PCC. A PCC may include an enclosed volume of 1-3% of the main combustion chamber volume, with a spark plug and a fuel passage located opposite one or more PCC discharge nozzles to create a relatively richer fuel-air mixture with relatively lower turbulence in the spark plug region and a relatively leaner fuel-air mixture with relatively high turbulence in the nozzle region, which can be reliably and efficiently ignited, resulting in a high velocity flame jet/torch emerging from the prechamber into the main chamber. The PCC may be threaded with a 22 mm×1.5 or ??-18 thread size, to allow the PCC to be screwed into a cylinder head in place of a spark plug.

Abstract: In certain embodiments, a two-stage precombustion chamber may be used to reduce engine NOx levels, with fueled precombustion chambers, while maintaining comparable engine power output and thermal efficiency. One or more fuel admission points may be located in either the first prechamber stage or the second prechamber stage. A more efficient overall combustion characterized by low levels of NOx formation may be achieved by a two-stage precombustion chamber system while generating very high energy flame jets emerging from the second prechamber stage into the main combustion chamber. A first prechamber stage may be substantially smaller than a second prechamber stage.

Abstract: In certain embodiments, a two-stage precombustion chamber may be used to reduce engine NOx levels, with fueled precombustion chambers, while maintaining comparable engine power output and thermal efficiency. One or more fuel admission points may be located in either the first prechamber stage or the second prechamber stage. A more efficient overall combustion characterized by low levels of NOx formation may be achieved by a two-stage precombustion chamber system while generating very high energy flame jets emerging from the second prechamber stage into the main combustion chamber. A first prechamber stage may be substantially smaller than a second prechamber stage.

Abstract: In certain embodiments, a unique method and pre-combustion chamber (PCC) structure may ensure very efficient flame propagation of lean fuel-air mixture in natural gas engines by reducing the amount of fuel admitted to the PCC. A PCC may include an enclosed volume of 1-3% of the main combustion chamber volume, with a spark plug and a fuel passage located opposite one or more PCC discharge nozzles to create a relatively richer fuel-air mixture with relatively lower turbulence in the spark plug region and a relatively leaner fuel-air mixture with relatively high turbulence in the nozzle region, which can be reliably and efficiently ignited, resulting in a high velocity flame jet/torch emerging from the prechamber into the main chamber. The PCC may be threaded with a 22 mm×1.5 or ??-18 thread size, to allow the PCC to be screwed into a cylinder head in place of a spark plug.

Abstract: In certain embodiments, a time-varying spark current ignition system can be applied to improve spark plug ignitability performance and durability as compared to conventional spark ignition systems. Two performance parameters of interest are spark plug life (durability) and spark plug ignitability. In certain embodiments, spark plug life can be extended by applying a spark current amplitude as low as possible without causing quenching of the flame kernel while it is traveling within an electrode gap and/or by applying spark current of a long enough duration to allow the spark/flame kernel to clear a spark plug gap. In certain embodiments, ignitability can be improved by applying a high enough spark current amplitude to sustain the flame kernel once outside the spark plug gap and/or by applying a spark current for long enough to sustain the flame kernel once outside the spark plug gap.

Abstract: In certain embodiments, a two-stage precombustion chamber may be used to reduce engine NOx levels, with fueled precombustion chambers, while maintaining comparable engine power output and thermal efficiency. One or more fuel admission points may be located in either the first prechamber stage or the second prechamber stage. A more efficient overall combustion characterized by low levels of NOx formation may be achieved by a two-stage precombustion chamber system while generating very high energy flame jets emerging from the second prechamber stage into the main combustion chamber. A first prechamber stage may be substantially smaller than a second prechamber stage.