Patent ID: 7162995
Filing Date: 2007-01-16
Classification: F02B,F02D,F02M,Y02T

Abstract:
1. A method of introducing a gaseous fuel into a high pressure direct injection internal combustion engine, said method comprising, during a cycle of said engine: (a) selecting an injection pressure for injecting said gaseous fuel from an injector into a charge at a charge pressure within a combustion chamber of said engine, said injection pressure resulting in an under-expanded gaseous fuel jet beyond and proximate to a nozzle of said injector, said fuel jet expanding at an injection speed beyond and proximate to said nozzle, said injection speed being, throughout an injection duration, in excess of a sonic speed of said gaseous fuel in said charge at said charge pressure; (b) at an injection crank angle near or at completion of a compression stroke of said cycle, directly injecting said gaseous fuel at said injection pressure for said injection duration into said charge, while avoiding substantial interference between said fuel jet and at least one of a cylinder and a piston, each of which partially defines said combustion chamber.