A method and a device for regulating the pressure of the combustion gas and/or exhaust gas of a machine, in particular an internal combustion engine. The combustion gas is supplied to the machine via a supply line and is discharged via an exhaust gas line, and the supply line and/or the exhaust gas line has a regulating device, the regulating device delimiting a pressure-regulated section of the supply line and/or the exhaust gas line, and wherein the pressure in each pressure-regulated section is measured at more than one point.

A method, controller, and internal combustion engine including the controller and operable in accordance with the method by: determining a temperature of a working liquid in an engine block circuit (31, 35) of the internal combustion engine (10), the working liquid comprising a cooling liquid or a lubrication liquid; operating the internal combustion engine (10); engaging a thermal load responsive to the temperature of the liquid being below a first temperature threshold, wherein engaging the thermal load comprises at least one of increasing a pumping load of the internal combustion engine (10), or changing an air/fuel ratio, thereby adding heat to the engine block circuit (31, 35); controlling the thermal load as a function of the temperature of the liquid; and disengaging at least a portion of the thermal load responsive to the temperature of the liquid being above the low temperature limit.

The present invention obtains a humidity measuring device capable of performing self-diagnosis with high reliability. This humidity measuring device 20 has a diagnosis processing unit 25 for performing self-diagnosis by using gas temperatures and gas humidities before and after a gas in an ambient atmosphere to be measured is heat-controlled. The diagnosis processing unit has a diagnosis start determining unit 26 for determining whether the self-diagnosis can be started on the basis of an exchange state in the ambient atmosphere to be measured and the gas temperature and the gas humidity before the gas in the ambient atmosphere to be measured is heat-controlled, and a diagnosis continuation determining unit 28 for determining whether the self-diagnosis can be continued on the basis of the gas temperature and the gas humidity that are heat-controlled during the self-diagnosis.

An internal combustion engine has a humidity sensor that is disposed in an intake passage of the internal combustion engine, a temperature sensor configured to detect an intake air temperature in a position of the humidity sensor, and a controller configured to correct an offset error of the sensor value by adding a correction value to the sensor value. The controller is configured to acquire the intake air temperatures respectively at a plurality of timings in a process of the intake air temperature changing, acquire the sensor values at the respective plurality of timings, calculate values excluding influences of temperature differences of the intake air temperatures from the respective sensor values as humidity index values respectively, and determine a correction value so that a variation degree of the humidity index values becomes small.

Methods and systems are provided for determining changes in a flow area of an exhaust gas recirculation (EGR) valve for EGR flow estimates due to soot accumulation on the EGR valve. In one example, a method includes indicating soot accumulation on the EGR valve based on a difference in EGR flow estimated with an intake oxygen sensor and with a pressure sensor coupled across the EGR valve. The determination of the difference of the EGR flow estimates may occur when the engine is not boosted.

A fuel estimation apparatus includes a combustion characteristic acquisition portion and a mixing ratio estimation portion. The combustion characteristic acquisition portion acquiring a combustion characteristic value indicating a physical amount relating to a combustion of an internal combustion engine acquires the combustion characteristic values of the combustions executed in different combustion conditions. The mixing ratio estimation portion estimates the mixing ratios of various components included in a fuel, based on the combustion characteristic values acquired by the combustion characteristic acquisition portion.

A combustion system controller controls an operation of a combustion system including an internal combustion engine. The combustion system controller includes a mixing ratio acquisition portion and a control portion. The mixing ratio acquisition portion acquires the mixing ratios of various components included in a fuel. The control portion controls the operation of the combustion system based on the mixing ratios acquired by the mixing ratio acquisition portion.

The present disclosure provides a method for controlling EGR rate of a low pressure EGR system, a system and a vehicle. The method calculates a molar concentration of water molecules of exhaust gas processed by EGR cooler, calculates a molar concentration of water molecules, obtains coefficient as to excess air, and calculates a molar volume ratio of air according to the coefficient. Under a maximum limit of humidity, an allowable EGR rate of the exhaust gas processed by the EGR cooler is determined and an allowable EGR rate of the mixed gas before entry into supercharger and/or compressor is also determined, a lower EGR rate between the two allowable rates is set as a maximum for application actual working conditions. The present disclosure solves a problem of condensation caused by an introduction of exhaust gas from the existing gasoline engine.

An evaporative emissions (EVAP) control system for a vehicle includes a purge pump configured to pump fuel vapor to a direct injection (DI) engine of the vehicle via a vapor line and a purge valve and a hydrocarbon (HC) sensor disposed configured to measure an amount of HC in the fuel vapor. The system also includes a controller configured to detect an HC vapor supply condition indicative of an operating condition of the Di engine where engine vacuum is less than an appropriate level for delivering the fuel vapor to the DI engine via the vapor line; and in response to detecting the HC vapor supply condition, controlling at least one of the purge pump and the purge valve, based on the measured amount of HC, to deliver a desired amount of fuel vapor to the DI engine to decrease particulate matter (PM) produced by the DI engine.

A device for predicting an exhaust gas recirculation rate of an internal combustion engine, which comprises an inlet system and at least one exhaust gas recirculation valve, is described. The device comprises a sensor arranged in the inlet system for determining the composition of the gas, a sensor for determining the position of the exhaust gas recirculation valve, and an evaluation apparatus. The evaluation apparatus is configured to determine and output a prediction of the exhaust gas recirculation rate based on a corrected estimate of the exhaust gas recirculation rate, wherein the estimate is based on the position of the exhaust gas recirculation valve and is corrected based on the composition of the gas as determined using the sensor.