Method for operating an internal combustion engine and internal combustion engine for such a method

A method for operating a direct-injection auto-ignition internal combustion engine, the internal combustion engine comprising at least one cylinder (1), a reciprocating piston (2) disposed in the cylinder (1), a cylinder head (3) and a combustion space (4) delimited by the cylinder (1), the piston (2) and the cylinder head (3), the piston (2) having a piston top (5) including a piston recess (6) which, has a transitional region with an essentially annular stepped space (7), and an injector (8) for injecting fuel into the combustion space (4), the injector (8) having a plurality of injection openings (25) forming jets (9, 9′) of fuel which are injected, distributed over the circumference of said combustion space (4), into the combustion space (4) along conically arranged jet axes (10), said method comprising the steps of:

• directing the injection jets (9, 9′) toward the stepped space (7) so that they are deflected there in such a way that a first part quantity (11) of fuel is deflected in an axial direction (14) and a radial direction (15) into the piston recess (6), a second part quantity (12) of fuel is deflected in the axial direction (14) and the radial direction (15) over the piston top (5) into the combustion space (4), and third part quantities (13, 13′) of fuel are deflected into a circumferential direction (16), the third part quantities (13, 13′) of adjacent fuel jets (9, 9′) impinging one onto the other in the circumferential direction (16) and subsequently being deflected radially inwardly, the jet cone angle, the start of injection and the injection duration being coordinated with one another and with the crank angle of the internal combustion engine in such a way that the third part quantities (13, 13′) of adjacent injection jets impinge one onto the other in the circumferential direction (16) with a velocity of at least 15 m/s.