Full expansion internal combustion engine

A method for operating a two-stroke, uniflow, full expansion internal combustion (IC) engine, the method comprising repeating a cylinder cycle, the cycle comprising the steps of:

• a) passing pressurized inlet air through an uncovered swirl inlet port and into a cylinder with a piston proximate the bottom of its reciprocal stroke (BDC) within the cylinder, and swirling the inlet air in tangential turbulent unidirectional flow within the cylinder,
• b) maintaining an exhaust port in an open position while the swirl inlet port is uncovered to provide scavenging of the cylinder by the inlet air,
• c) advancing the piston upward to cover the inlet port at a fixed closing cycle timing,
• d) further maintaining the exhaust port in an open position after covering the inlet port for a substantial portion of the remaining stroke movement of the piston toward top dead center (TDC);
• e) closing the exhaust port at a fixed closing cycle timing,
• f)compressing the inlet air between the piston and the cylinder head as the piston advances toward top dead center at a constant high compression ratio of about 15:1 to about 20:1,
• g) dispersing a fuel near the end of the compression stroke at a lean burning fuel to air ratio of about 0.6:1 relative to a stoicheometric fuel:air ratio of 1:1,
• h) spark igniting and combusting the air-fuel mixture to initiate the power stroke,
• i) opening the exhaust port near the end of the power stroke at a fixed opening cycle timing to exhaust pressurized combustion gases, and
• j) uncovering the inlet swirl port as the piston approaches the bottom of its power stroke at a fixed opening cycle timing.