Abstract: A method of improving scavenging operation of a two-stroke internal combustion engine. The exhaust pressure of the engine is analyzed to determine if there is a pulsation frequency. Acoustic modeling is used to design an absorber. An appropriately designed side branch absorber may be attached to the exhaust manifold.

Abstract: A method and system for controlling an engine that drives a reciprocating compressor, such as the large compressors used for natural gas transmission. A controller receives data from the compressor representing operation conditions, such as load step, suction pressure, and discharge pressure. The controller then calculates engine control parameters, such as air intake and spark timing, based on the compressor data to optimize engine performance and emissions.

Abstract: An engine control strategy that ensures that NOx emissions from the engine will be maintained at an acceptable level. The control strategy is based on a two-dimensional fuel-air curve, in which air manifold pressure (AMP) is a function of fuel header pressure and engine speed. The control strategy provides for closed loop NOx adjustment to a base AMP value derived from the fuel-air curve.

Abstract: A fuel injector timing tool has an elongated tubular member on which a measurement device may be mounted. A lower end of the tubular member is attached to a base member disposed perpendicularly to the tubular member and has an open end that only partially circumscribes a plunger follower slidably disposed on a retainer element of the fuel injector. The timing tool permits ready access to an adjustable ball stud and associated lock nut mounted in a plunger actuator end of an injector rocker arm so that accurate plunger position can be set while the timing tool remains in place on the retainer element of the fuel injector.

Abstract: A method of balancing combustion among cylinders of an internal combustion engine. For each cylinder, a normalized peak firing pressure is calculated as the ratio of its peak firing pressure to its combustion pressure. Each cylinder's normalized peak firing pressure is compared to a target value for normalized peak firing pressure. The fuel flow is adjusted to any cylinder whose normalized peak firing pressure is not substantially equal to the target value.

Abstract: A method of operating a two-cycle internal combustion engine under low load conditions. A throttle is placed at the intake air system to reduce air intake into the engine cylinders. A pump is placed in the exhaust system, such that it creates reduced pressure downstream of the exhaust valves. In this manner, when the air intake ports close, the exhaust is evacuated and the air trapped in the cylinder is reduced. This permits fuel to be reduced so that the engine may operate in a low load state without losing combustion.