INTERNALLY COOLED EXHAUST GAS RECIRCULATION SYSTEM FOR INTERNAL COMBUSTION ENGINE AND METHOD THEREOF

摘要

An internal combustion engine is provided equipped with an exhaust gas recirculating (EGR) system and means for internally cooling the exhaust gases by a spray of atomized water into the recirculated exhaust gases prior to ignition. The atomized water spray may be in the intake manifold or directly in the cylinder. The engine may employ spark or compression ignition. The internal combustion engine operates with compression ratios greater than 12:1 and lean air:fuel ratios. Also provided is a method for controlling the amount of exhaust gas recirculated in the engine, and for controlling the amount of water added. The inventive engines have elevated thermodynamic efficiencies and favorable NOx emissions.

主权项

1. An internal combustion engine comprising:
at least one cylinder wherein each cylinder has a combustion chamber, a piston, an air intake valve, and an exhaust valve, wherein the mechanical compression ratio in each cylinder is greater than 12:1 and less than about 40:1; an air intake track in communication with each air intake valve; an exhaust track in communication with each exhaust valve; a fuel handling system with at least one fuel injector for injecting fuel into the combustion chamber or intake track, wherein the fuel handing system provides an air to fuel ratio having a ratio of air to fuel (λ) greater than 1 and less than 7.0; an ignition system for igniting the fuel in the combustion chamber at an end portion of a compression stroke of the piston; an exhaust gas recirculating (EGR) means for recirculating exhaust gases from the exhaust port to the engine intake; and a cooling means for cooling the recirculated exhaust gases by direct contact with a predetermined quantity of atomized water injected into the EGR track.