Engine system, piston, and operating method for pseudo-tumble mixing of hydrogen fuel and air

An engine system comprising:

• a gaseous fuel supply;
• an engine housing forming a cylinder;
• a piston within the cylinder movable between a bottom-dead-center position and a top-dead-center position, the piston defining a piston center axis and including a piston rim extending circumferentially around a combustion bowl, a center cone within the combustion bowl, a bowl floor, and a reentrant bowl wall extending to a bowl edge extending from the bowl outer wall to the piston rim and defining a bowl throat opening to admit a fuel and air from a space defined above the piston rim directly into the combustion bowl, and the piston defining a bowl max radius dimension and a bowl throat radius dimension that is from 50% to 80% of the bowl max radius dimension;
• and
• a fuel injector fluid coupled to the gaseous fuel supply and extending into the cylinder, and the fuel injector including at least one fuel outlet hole oriented to target the center cone of the piston.

A piston for an internal combustion engine comprising:

• a piston crown including a piston outer surface extending circumferentially around a piston center axis, and a piston rim extending circumferentially around a combustion bowl, a center cone within the combustion bowl, a bowl floor, and a bowl outer wall extending reentrantly to a bowl edge extending from the bowl outer wall to the piston rim and defining a bowl throat opening to admit a fuel and air from a space defined above the piston rim directly into the combustion bowl;
• the piston defining a bowl max radius dimension extending from the piston center axis to the bowl outer wall, a throat radius dimension extending from the piston center axis to the bowl edge, and a piston radius dimension;
• and
• the throat radius dimension is from 50% to 80% of the bowl max radius dimension, and from 40% to 70% of the piston radius dimension.