Patent ID: 8973539
Filing Date: 2015-03-10
Classification: F02B,Y02T

Abstract:
1. 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 swirl inlet port at a fixed closing cycle timing, d) further maintaining the exhaust port in an open position after covering the swirl 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 pressure ratio of about 10:1 to about 25:1, g) dispersing a fuel near the end of the compression stroke at a lean burning fuel to air ratio of about 0.04:1 to about 1:1, 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.