Cold-Start Strategies for Opposed-Piston Engines

摘要

A strategy to cold-start an opposed-piston engine includes, before injecting fuel, preventing air flow through the engine while cranking the engine to heat air retained in the engine, followed by controlling mass air flow through and fuel injection into a cylinder of the engine according to cold-start schedules so as to create and preserve heat for stable engine firing and transition to an idling state of operation.

主权项

1. A method of operating an opposed-piston engine with one or more cylinders, in which each cylinder has a piston-controlled exhaust port coupled to an exhaust subsystem and a piston-controlled intake port coupled to a charge air subsystem, a pair of pistons disposed for opposing movement in a bore of the cylinder, and one or more fuel injectors disposed for injecting fuel into the cylinder, the method comprising:
receiving a signal to start the engine; detecting a cold-start condition, followed by: before fuel is injected, limiting charge air flow through the cylinder and heating air retained in the cylinder by cranking the engine; and then, injecting fuel into a combustion space between opposing end surfaces of pistons in the cylinder according to a cold-start schedule; providing a progressively increasing flow of charge air through the cylinder until an engine idling state is reached; and, injecting fuel into the combustion space according to an idling schedule.