A diesel engine is provided with an EGR line G3 configured to recirculate a portion of exhaust gas, discharged from an engine body 11, to the engine body 11 as combustion gas, an EGR cooler 16 provided in the EGR line G3 and configured to cool exhaust gas by coolant, a coolant supply device configured to supply coolant to the EGR cooler 16, and a control device 30 configured to activate the coolant supply device when the engine body 11 is in operation and a temperature of the engine body 11 is lower or equal to a preset prescribed temperature.

A controller calculates a specific humidity of an intake air based on a relative humidity of the intake air, an intake air temperature, and an intake air pressure. Then the controller calculates a water vapor amount in the intake air based on the specific humidity and a mass flow rate of the intake air obtained from an air intake rate. By calculating the water vapor amount in the intake air based on information that directly represents the status of the intake air, this water vapor amount may be calculated more accurately. As a result, a generation amount of condensed water may be estimated more accurately. Therefore, accumulation of condensed water may be suppressed while recirculating as much of a low pressure exhaust gas as possible, and thus fuel economy may be sufficiently improved.

A controller calculates a specific humidity of an intake air based on a relative humidity of the intake air, an intake air temperature, and an intake air pressure. Then the controller calculates a water vapor amount in the intake air based on the specific humidity and a mass flow rate of the intake air obtained from an air intake rate. By calculating the water vapor amount in the intake air based on information that directly represents the status of the intake air, this water vapor amount may be calculated more accurately. As a result, a generation amount of condensed water may be estimated more accurately. Therefore, accumulation of condensed water may be suppressed while recirculating as much of a low pressure exhaust gas as possible, and thus fuel economy may be sufficiently improved.

A sealing system for an exhaust gas recirculation valve, the exhaust gas recirculation valve including a housing and a valve stem disposed in the housing, the sealing system being disposed between the housing and the valve stem in order to prevent exhaust gas from entering a valve body interior. The sealing system includes at least two sealing assemblies. An exhaust gas recirculation valve includes the sealing system, and the sealing system effectively prevents exhaust gas from leaking into the valve body interior, and effectively prevents carbon deposits from sticking to the valve stem or entering the valve body interior, so as to increase the lifespan and reliability of the exhaust gas recirculation valve.

The invention relates to a valve device for a motor vehicle, comprising a housing, a flow channel located in the housing, a flap arranged in the flow channel for closing the flow channel, the flap having regions in which a pin penetrating the flap is fastened and the pin being rotatably mounted in the housing, and a valve seat, which is arranged in the flow channel and which is in contact with the flap when the latter is in the closed position. The flow channel is provided with a plasma coating which renders it hydrophobic or hydrophilic.

Aspects of the disclosure relate to providing an EGR cooler including a barrier layer applied to EGR cooler components while allowing sufficient heat transfer between exhaust gases and the cooling medium. A barrier layer may be applied onto particular surfaces of the EGR cooler components to prevent deposition of hydrocarbons or soot on the EGR cooler components. In some arrangements, the barrier layer may comprise a refractory solid oxide. In other arrangements, an EGR cooler may comprise a catalytic barrier layer. The catalytic barrier layer may include a refractory solid oxide and a platinum group metal or mixed metal oxide to prevent accumulation of varnish material deposited onto EGR cooler components.

Aspects of the disclosure relate to providing an EGR cooler including a barrier layer applied to EGR cooler components while allowing sufficient heat transfer between exhaust gases and the cooling medium. A barrier layer may be applied onto particular surfaces of the EGR cooler components to prevent deposition of hydrocarbons or soot on the EGR cooler components. In some arrangements, the barrier layer may comprise a refractory solid oxide. In other arrangements, an EGR cooler may comprise a catalytic barrier layer. The catalytic barrier layer may include a refractory solid oxide and a platinum group metal or mixed metal oxide to prevent accumulation of varnish material deposited onto EGR cooler components.

A determination is made whether or not the condition that the amount V of condensed water remaining in an intake passage has exceeded a predetermined upper limit has been met, based on an input parameter associated with the amount V. If, during an engine operation in an unsupercharged mode, a determination is made that the condition has been met, a condensed water discharging operation of a supercharger is performed such that the condensed water remaining is discharged to a cylinder of the engine through operation of the supercharger.

A determination is made whether or not the condition that the amount V of condensed water remaining in an intake passage has exceeded a predetermined upper limit has been met, based on an input parameter associated with the amount V. If, during an engine operation in an unsupercharged mode, a determination is made that the condition has been met, a condensed water discharging operation of a supercharger is performed such that the condensed water remaining is discharged to a cylinder of the engine through operation of the supercharger.

A first member has a plated layer. A second member is pressed against the plated layer and causes a tensile stress in the first member. A breakage probability is a probability of breakage of the plated layer caused by the tensile stress. A characteristic line represents a relationship between an elastic modulus of the plated layer and the breakage probability. A characteristic slope of the characteristic line is a ratio of an increase in the breakage probability to a decrease in the elastic modulus. A characteristic change point appears on the characteristic line at which the elastic slope increases to exceed a predetermined slope as the elastic modulus gradually decreases. A characteristic change elastic modulus is the elastic modulus at the characteristic change point. The plated layer contains at least a chromium component and has the elastic modulus larger than the characteristic change elastic modulus.