WORK VEHICLE COMPRESSION IGNITION POWER SYSTEM HAVING THERMALLY STRATIFIED ENGINE COMBUSTION CHAMBERS

A power system includes an intake arrangement and a compression ignition engine including piston-cylinder sets. Each piston-cylinder set includes: a cylinder; a piston positioned within the cylinder to form a combustion chamber in between; an intake valve configured to open and close the intake port; an exhaust valve configured to open and close the exhaust port; and a fuel injector. During an exhaust stroke, the exhaust valve is opened to enable exhaust gas to flow out; during an initial portion of an intake stroke, the intake valve is opened to enable the intake air to flow into the combustion chamber, and during a further portion of the intake stroke, the intake valve is closed and the exhaust valve is opened to enable a portion of the exhaust gas to flow back into the combustion chamber in order to create thermally stratified layers of intake gas and exhaust gas.