Two-stroke engine and four-stroke engine

摘要

A two-stroke engine (1) includes a cylinder (2) having a scavenging port (23) and an exhaust port (24), a piston (3) provided in the cylinder (2), a first ejection part (61) for ejecting liquid ammonia into a combustion chamber (20), and a supercharger (5) for pressurizing a suction gas to generate a scavenging gas. In the two-stroke engine (1), the first ejection part (61) ejects liquid ammonia into the combustion chamber (20) within a period of time from when supply of the scavenging gas through the scavenging port (23) into the combustion chamber (20) is started until when the piston (3) next reaches top dead center. It is thus possible to reduce the temperature of gas within the combustion chamber (20) by the heat of vaporization of the liquid ammonia, reduce the pressure in the combustion chamber (20) during compression, and reduce the amount of compression work.

主权项

1. A two-stroke engine comprising:
a cylinder; a piston provided in said cylinder; a supercharger for pressurizing a suction gas to generate a scavenging gas; a scavenging port formed in said cylinder and for supplying said scavenging gas from said supercharger into a combustion chamber that is a space enclosed by said cylinder and an upper surface of said piston; an exhaust port formed in said cylinder and for exhausting gas within said combustion chamber out of said combustion chamber; and a liquid ammonia source and at least one ejection part for ejecting liquid ammonia from said liquid ammonia source into said combustion chamber within a period of time from when supply of said scavenging gas through said scavenging port into said combustion chamber is started until when said piston next reaches top dead center, said at least one ejection part being configured to direct said liquid ammonia so as to cool said scavenging gas; and said at least one ejection part further ejecting fluid fuel into said combustion chamber when said piston is positioned in a vicinity of said top dead center, so as to cause said fluid fuel to ignite spontaneously in said combustion chamber, said fluid fuel containing liquid ammonia from said liquid ammonia source.