An EGR cooler includes a tube assembly formed by stacking a plurality of tubes in which exhaust gas flows and a cover plate having a mounting portion formed concavely to mount the tube assembly thereon. A baffle is mounted at the tube assembly and adjusts flow of coolant inflow from a cylinder block. An inlet cover is installed on a first side of an outer surface of the cover plate to supply the exhaust gas to each tube and an outlet cover is installed on a second side of outer surface of the cover plate to exhaust the exhaust gas from each tube. At least one coolant passage in which the coolant flows is formed between the plurality of tubes.

An EGR cooler includes a tube assembly formed by stacking a plurality of tubes in which exhaust gas flows and a cover plate having a mounting portion formed concavely to mount the tube assembly thereon. A baffle is mounted at the tube assembly and adjusts flow of coolant inflow from a cylinder block. An inlet cover is installed on a first side of an outer surface of the cover plate to supply the exhaust gas to each tube and an outlet cover is installed on a second side of outer surface of the cover plate to exhaust the exhaust gas from each tube. At least one coolant passage in which the coolant flows is formed between the plurality of tubes.

An exhaust gas recirculation system for a multi-cylinder engine is provided, which includes an exhaust manifold connected to a cylinder head, a catalyst connected to a downstream end of the exhaust manifold in terms of an exhaust gas flow, an EGR gas outlet provided downstream of the catalyst, an in-head EGR passage penetrating the cylinder head, and an EGR pipe extending from the EGR gas outlet and directly connected to an inlet of the in-head EGR passage to lead EGR gas thereto. The catalyst is disposed so that the exhaust gas flows therein from a first side to a second side in an engine cylinder lined-up direction. The EGR gas outlet is located on the second side with respect to the center of the engine in the cylinder lined-up direction, and the inlet of the in-head EGR passage is located in the first side with respect to the engine center.

An exhaust gas recirculation structure includes an EGR cooler and an EGR duct, and the EGR duct includes an inflow portion into which the exhaust gas flowing out from the EGR cooler flows, a flow path, and an outflow portion from which the exhaust gas flows out. The flow path is provided such that the height on the side of the inflow portion is lower than the height on the side of the outflow portion, and has a region in which the distance between the center line of a flow path cross section of the flow path and a line along the lowest end in the height direction gradually increases from the outflow portion side toward the inflow portion side.

An exhaust gas recirculation structure includes an EGR cooler and an EGR duct, and the EGR duct includes an inflow portion into which the exhaust gas flowing out from the EGR cooler flows, a flow path, and an outflow portion from which the exhaust gas flows out. The flow path is provided such that the height on the side of the inflow portion is lower than the height on the side of the outflow portion, and has a region in which the distance between the center line of a flow path cross section of the flow path and a line along the lowest end in the height direction gradually increases from the outflow portion side toward the inflow portion side.

An engine 1 includes an exhaust manifold, an intake manifold, and an EGR device configured to supply EGR gas from the exhaust manifold to the intake manifold. An upper end of the EGR cooler extended downward is attached to a downwardly extending attachment part provided to the exhaust manifold.

An engine 1 includes an exhaust manifold, an intake manifold, and an EGR device configured to supply EGR gas from the exhaust manifold to the intake manifold. An upper end of the EGR cooler extended downward is attached to a downwardly extending attachment part provided to the exhaust manifold.

A cylinder head cooling system may include a main water jacket formed on a cylinder head, an exhaust port formed on the cylinder head, and an exhaust port water jacket formed to cool the exhaust port, wherein, the exhaust port water jacket includes an inlet that communicates with the main water jacket and a plurality of outlets separated from the main water jacket.

An intake device for an engine is provided which can inhibit excessive cooling of EGR gas. In the intake device including an intake passage, an EGR passage, and an EGR cooler, the intake passage is provided with a lateral-side intake passage portion provided on one side of an engine body in a vehicle width direction, the EGR passage is provided with a downstream-side EGR passage portion defining the EGR passage on a downstream side of the EGR cooler and provided on the one side of the engine body in the vehicle width direction, and the downstream-side EGR passage portion is disposed such that at least a portion thereof is positioned rearward of the lateral-side intake passage portion and overlaps with the lateral-side intake passage portion when seen from the front of a vehicle.

Disclosed is a method of preventing fouling of an exhaust gas recirculation (EGR) cooler of an engine including after a vehicle including the engine reaches a reference mileage, operating, by a controller, an exhaust brake device of the vehicle and blocking the discharge of exhaust gas of the engine, after the exhaust brake device is operated, closing, by the controller, an EGR valve that provides the exhaust gas of the engine to an EGR cooler of an EGR system of the engine, and before the operation of the exhaust brake device is stopped, removing, by the controller, a deposition layer generated in the EGR cooler, by opening the EGR valve.