An engine device in which an exhaust gas purification device can be disposed without substantially increasing mounting width dimensions (height, lateral width, front and rear width) of an engine. The engine device includes the exhaust gas purification device connected to an exhaust manifold of the engine, an oil pan disposed on a bottom of the engine, a support body for linking the exhaust gas purification device to the oil pan, so that the exhaust gas purification device is supported by the oil pan.

Active control of one or more exhaust gas recirculation loops is provided to manage and EGR fraction in the charge flow to produce desired operating conditions and/or provide diagnostics in response to at least one of an oxygen concentration and a NOx concentration in the charge flow and in the exhaust flow.

Methods and systems are provided for exhaust gas heat recovery at a split exhaust gas heat exchanger. Exhaust gas may flow in both directions through an exhaust bypass passage and the heat exchanger coupled to the bypass passage. Warm or cold EGR may be delivered from the exhaust passage to the engine intake manifold and heat from the exhaust gas may be recovered at the heat exchanger.

Methods and systems are provided for exhaust gas heat recovery at a split exhaust gas heat exchanger. Exhaust gas may flow in both directions through an exhaust bypass passage and the heat exchanger coupled to the bypass passage. Warm or cold EGR may be delivered from the exhaust passage to the engine intake manifold and heat from the exhaust gas may be recovered at the heat exchanger.

An engine cooling system may include a main intake line for supplying external air to an intake manifold attached to an engine including a cylinder block and a cylinder head, a supplementary intake line branched from one side of the main intake line and joined to the other side of the main intake line, an intake route control valve in the main intake line, a main exhaust line for flowing exhaust gas from an exhaust manifold, an exhaust route control valve in the main exhaust line, a turbocharger, an intercooler mounted to the supplementary intake line on a downstream side of the turbocharger, an EGR cooler branched from the exhaust manifold for recirculating the exhaust gas and provided in an EGR line connected to the main intake line; and a cooling line for flowing a coolant supplied from a water pump to cool the EGR cooler, the exhaust route control valve and/or the turbine housing of the turbocharger.

The objective of the present invention is to provide a control device for an internal combustion engine that is able to provide a more stable combustion state by suitably setting the amount of recirculated exhaust gas. The present invention is an internal combustion engine control device equipped with air cylinders and an EGR mechanism that returns exhaust gas emitted from the air cylinders to the intake side of the air cylinders, and is characterized by being equipped with an EGR control unit that controls the EGR flow volume of the EGR mechanism, and a humidity detection means that directly or indirectly detects the humidity of outside air supplied to the air cylinders, with the EGR control unit calculating the moisture amount in the outside air and the moisture amount in the recirculated exhaust gas, and controlling the EGR mechanism on the basis of: a stable combustion limit air cylinder mass, which is set in accordance with the combustion state in the air cylinders; the mass of the air introduced into the air cylinders; the mass of the fuel; and the moisture amounts.

A system and method for preventing a failure of an exhaust heat recovery device are provided. The method includes operating a sole exhaust heat recovery mode when cooling water has a temperature less than a warm-up reference temperature to introduce all exhaust gas flowing from a DPF into the exhaust heat recovery device where the exhaust gas exchanges heat with the cooling water. Additionally, a passage through which the exhaust gas bypasses the exhaust heat recovery device is opened when the exhaust gas at a rear of the DPF has a temperature greater than the warm-up reference temperature during the sole exhaust heat recovery mode.

The EGR cooling structure includes a cylinder block having cylinders, and a cylinder head into which exhaust gas exhausted from the cylinders is collected. An exhaust emission control device is provided for purifying the exhaust gas exhausted from the cylinder head, and an EGR pipe is provided through which EGR gas of a part of the purified exhaust gas is introduced into an intake system. An EGR cooler is provided in the EGR pipe and cools the EGR gas with the cooling liquid. An exhaust gas passage leading from the cylinders to the exhaust gas purification device is curved when seen from a side, and the EGR cooler is disposed in the space surrounded by the cylinder block, the cylinder head, and the exhaust gas purification device.

The EGR cooling structure includes a cylinder block having cylinders, and a cylinder head into which exhaust gas exhausted from the cylinders is collected. An exhaust emission control device is provided for purifying the exhaust gas exhausted from the cylinder head, and an EGR pipe is provided through which EGR gas of a part of the purified exhaust gas is introduced into an intake system. An EGR cooler is provided in the EGR pipe and cools the EGR gas with the cooling liquid. An exhaust gas passage leading from the cylinders to the exhaust gas purification device is curved when seen from a side, and the EGR cooler is disposed in the space surrounded by the cylinder block, the cylinder head, and the exhaust gas purification device.

An exhaust gas recirculation (EGR) cooler is provided and includes a plurality of tubes that are spaced apart from each other and a cavity that is disposed on an engine to receive the plurality of tubes. A coolant guide guides a coolant to the plurality of tubes and a cover then closes the cavity. The cavity has an inlet port that communicates with a water jacket of the engine and the cavity receives the coolant from the water jacket of the engine through the inlet port.