Injection control method and combustion system for diesel-ignited high-pressure direct injection liquid ammonia internal combustion engine

Abstract

The present application relates to a diesel-ignited high-pressure direct injection liquid ammonia internal combustion engine injection control method and combustion system, belonging to the field of internal combustion engine technology. The diesel-ignited high-pressure direct injection liquid ammonia internal combustion engine combustion control method includes the following steps: when the internal combustion engine is started or under low-load conditions, the internal combustion engine operates in pure diesel mode; when the internal combustion engine meets the liquid ammonia injection conditions and the piston moves to the vicinity of the compression top dead center, the diesel-ammonia nozzle is controlled to open, and a predetermined amount of diesel and liquid ammonia are sprayed into the main combustion chamber for compression combustion; after the diesel is compressed and ignited, the liquid ammonia is heated and flash-boiled in the main combustion chamber and ignited by the flame of the diesel combustion to form a stable diffusion combustion. Since the diffusion combustion mode of diesel-ignited ammonia fuel is adopted, the problems of difficult combustion and insufficient reaction of ammonia fuel are improved. Since ammonia fuel is used, the octane number of ammonia fuel is higher than that of diesel, so the ability of ammonia fuel to resist detonation is better than that of diesel, which can allow the internal combustion engine to set a higher compression ratio, thereby improving the power density and thermal efficiency of the internal combustion engine.

Images