Southwest Research Institute

Steven Almaraz

Jess Witman Gingrich

Raphael Gukelberger

Barrett Wade Mangold

Forest C Gibson

A method of operating a split intake D-EGR (dedicated exhaust gas recirculation) engine having at least one D-EGR cylinder and a number of non-EGR cylinders. If the engine is in a low load operating condition, either of two cylinder deactivation modes may be performed. In first cylinder deactivation mode, the D-EGR cylinder(s) are deactivated by disabling fuel delivery to the D-EGR cylinder(s), closing a D-EGR throttle, closing a D-EGR valve, and operating a three-way valve on the main exhaust line such that no exhaust from the D-EGR cylinder(s) is exhausted. In a second cylinder deactivation mode, the non-EGR cylinders are deactivated by disabling fuel delivery to the non-EGR cylinders, opening the D-EGR throttle, closing the D-EGR valve, and operating the three-way valve such that no exhaust from the main cylinders is exhausted.

Internal combustion engine having dedicated EGR cylinder(s) with split intake and cylinder deactivation at low loads

A dedicated exhaust gas recirculation configuration that provides reduced exhaust gas recirculation (EGR) backflow and reduced fresh air backflow. One-way valves are positioned in the EGR loop to reduce or avoid fresh-air backflow into the dedicated exhaust gas recirculating cylinder and/or positioned in the engine intake passage to reduce or avoid dedicated cylinder exhaust gas backflow into the intake passage.

Dedicated exhaust gas recirculation configuration for reduced EGR and fresh air backflow

A four stroke internal combustion engine with dedicated exhaust gas recirculation and method of operating such engine, wherein the engine comprises a plurality of combustion cylinders including main cylinders and a dedicated exhaust gas recirculation cylinder, wherein each cylinder includes a piston; a crankshaft, which is rotatable in a direction, and defines a main crankshaft axis, and includes a plurality of crankpins. Each of the crankpins is coupled to at least one of the pistons. The crankpins affixed to the pistons of the main cylinders are spaced at an interval around the main crankshaft axis. The crankpin affixed to the piston of the dedicated exhaust gas recirculation cylinder is spaced at an offset of 5 to 50 degrees from the interval in either direction relative to the direction of crankshaft rotation.

Crank pin offset in dedicated exhaust gas engines

The present disclosure relates to methods, apparatuses and systems to manage exhaust gas expelled from cylinders of an internal combustion engine. An exemplary system may comprise at least one cylinder of the engine configured to operate as a dedicated exhaust gas recirculation (EGR) cylinder, and wherein substantially all exhaust gas expelled from the dedicated EGR cylinder is recirculated to an intake system of the engine. In one embodiment, the system may include a flow restrictor configured and arranged to restrict a flow of the recirculated exhaust gas to the dedicated EGR cylinder without restricting a flow of the recirculated exhaust gas to the remaining cylinders of the engine. In another embodiment, exhaust gas may be expelled from the dedicated EGR cylinder in pulsations, and the intake system may be configured to reduce an amplitude of the pulsations of the exhaust gas expelled from the dedicated EGR cylinder.

Dedicated EGR control strategy for improved EGR distribution and engine performance

An integrated water-gas-shift (WGS) and emissions control device (ECD) catalyst for treating exhaust from an internal combustion engine. The engine is assumed to have an EGR loop, such that exhaust is recirculated back to the engine's intake. A WGS catalyst on the EGR loop, for conditioning the EGR flow, is integrated with a catalyzed ECD on the main exhaust line, for reducing pollutant emissions.

Integrated WGS/ECD exhaust treatment device for internal combustion engine having an EGR loop

The present disclosure relates to methods, apparatuses and systems to manage exhaust gas expelled from an internal combustion engine. More particularly, the present disclosure provides an exhaust gas recirculation apparatus to distribute recirculated exhaust gas in an air stream to be introduced to an internal combustion engine, with the apparatus comprising an intake passage defined by a wall structure, the wall structure including a plurality of apertures therein configured to distribute recirculated exhaust gas into the intake passage.

Growing community of inventors

Seguin, TX, United States of America

Steven Almaraz