Thermal management of aftertreatment devices of opposed-piston engines under motoring conditions
AssigneeAchates Power, Inc.
InventorsFabien G. Redon, Arunandan Sharma
Life of this patent
Estimating the term…
Abstract
A method of operating a two-stroke cycle, opposed-piston engine comprising a pumping device coupled to pump air to cylinders of the engine through a charge air cooler and an aftertreatment system of thermally-activated devices coupled to receive exhaust from the cylinders by which a thermal state of the exhaust sufficient to sustain thermal activation of one or more of the aftertreatment system devices may be maintained during a deceleration or motoring condition of operation by reducing the mass airflow to the engine.
Claims20
A method of operating a two-stroke cycle, opposed-piston engine comprising a control unit to execute the method, a supercharger coupled to pump air to cylinders of the engine through a charge air cooler, a bypass channel to recirculate charge air from an outlet of the supercharger to an inlet of the supercharger, and an aftertreatment system of thermally-activated devices coupled to receive exhaust from the cylinders, the method comprising:
- injecting fuel into the engine while operating the engine in a two-stroke cycle mode;
- operating the supercharger to provide a mass airflow into the engine;
- transporting a mass exhaust flow from the engine to the aftertreatment system;
- ceasing fuel injection into the engine while motoring the engine;
- and,
- maintaining a thermal state of the mass exhaust flow sufficient to sustain thermal activation of one or more of the aftertreatment system devices during motoring of the engine by recirculating a portion of the mass airflow through the bypass channel to the inlet of the supercharger.
A method of operating a fuel-injected, opposed-piston engine comprising a control unit to execute the method, a supercharger coupled to pump air to cylinders of the engine through a charge air cooler, a bypass channel to recirculate charge air from an outlet of the supercharger to an inlet of the supercharger, and an aftertreatment system of thermally-activated devices coupled to receive exhaust from the cylinders, the method comprising:
- injecting fuel into the engine while operating the engine in a two-stroke cycle mode;
- operating the supercharger to provide a mass airflow to the engine;
- transporting a mass exhaust flow from the engine to an inlet of the aftertreatment system;
- ceasing fuel injection into the engine while operating the engine;
- and,
- maintaining a thermal state of the mass exhaust flow sufficient to sustain thermal activation of one or more of the aftertreatment system devices during cessation of fuel injection by recirculating a portion of the mass airflow through the bypass channel to the inlet of the supercharger.
A method of operating a two-stroke, opposed-piston engine comprising a control unit to execute the method, a supercharger coupled to pump air to cylinders of the engine through a charge air cooler, a bypass channel to recirculate charge air from an outlet of the supercharger to an inlet of the supercharger, and an aftertreatment system of thermally-activated devices coupled to receive exhaust from the cylinders, the method comprising:
- injecting fuel into the engine while operating the engine in a two-stroke cycle mode;
- operating the supercharger to provide a mass airflow to the engine;
- transporting a mass exhaust flow from the engine to an inlet of the aftertreatment system;
- detecting an exhaust flow reduction condition of engine operation;
- ceasing fuel injection in response to the exhaust flow reduction condition of engine operation;
- and,
- maintaining a thermal state of the mass exhaust flow sufficient to sustain thermal activation of one or more of the aftertreatment system devices during the exhaust flow reduction condition of operation by recirculating a portion of the mass airflow through the bypass channel to the inlet of the supercharger.
Dependencies are inferred from the claim text.