An aircraft diesel engine may be operated at a minimal fuel rate. Shaft output power of the engine may be reduced by initiating combustion during the compression stroke. Combustion may be initiated during the compression stroke by advancing fuel injection, splitting fuel injection, and/or manipulating individual injection quantities. Initiating combustion during the compression stroke may slew torque generation to the compression stroke.

Provided is a compressor capable of calculating the correct time remaining before maintenance. The compressor is provided with: a compressor body that compresses fluid; a motor that drives the compressor body; a temperature sensor that detects the temperature of the compressor; a pressure sensor that detects the pressure of the compressed fluid outputted from the compressor body; and a calculation unit that calculates the time remaining before maintenance for the compressor body, using the temperature of the compressor and the pressure of the compressed fluid assigned with respective predetermined weights. The calculation unit changes the weighting of the temperature according to the pressure of the compressed fluid or the operation rate of the compressor body.

A fuel property determination apparatus for an internal combustion engine is applied to an internal combustion engine that is equipped with an ignition plug and an ignition timing controller. An electronic control unit provided in the fuel property determination apparatus executes a determination process of making a determination on a property of a fuel supplied to the internal combustion engine based on an ignition sufficiency ratio, during a predetermined period after startup of the internal combustion engine. The electronic control unit is configured to determine that the property of the fuel is heavy when a determination index value that is obtained by subjecting the ignition sufficiency ratio to a smoothing process is equal to or larger than a predetermined threshold. The electronic control unit is configured to set a smoothing coefficient to a value corresponding to each of a first period, a second period, and a third period.

A method for analyzing a fluid that flows from a chamber, in particular a combustion chamber, of an internal combustion engine into a fluid guide. The internal combustion engine includes at least one element, in particular an injector, for the supply of fuel. The analysis takes place with the aid of a sensor, in particular a lambda sensor, on which the fluid in the fluid guide acts. The analysis takes place during cranking of the internal combustion engine, and the fluid acting on the sensor is not influenced by fuel that is supplied in a controlled manner.

An engine control system of a vehicle includes a fuel control module that controls fuel injection of a first cylinder of an engine based on a first target air/fuel ratio that is fuel lean relative to a stoichiometric air/fuel ratio and that controls fuel injection of a second cylinder of the engine based on a second target air/fuel ratio that is fuel rich relative to stoichiometry. The first cylinder outputs exhaust to a first three way catalyst (TWC), and the second cylinder outputs exhaust to an exhaust gas recirculation (EGR) valve. An EGR control module controls opening of the EGR valve to: (i) a second TWC that reacts with nitrogen oxides (NOx) in the exhaust and outputs ammonia to a selective catalytic reduction (SCR) catalyst; and (ii) a conduit that recirculates exhaust back to an intake system of the engine.

The present disclosure provides a method for adjusting the operation of an internal combustion engine comprising: determining a gradient of an overrun-air line based on an ambient condition and a current operating point; determining a value for a cylinder air mass situated in a cylinder after closure of the gas exchange valves; and using the determined cylinder air mass to adjust one or more operating parameters of the internal combustion engine. The overrun-air line may correspond to an air mass situated in the respective cylinder after closure of the gas exchange valves at predefined operating temperature for the engine, when the engine is operated briefly without fuel metering and combustion. Determining a cylinder air mass may be based at least in part on the current operating point and the current ambient value of the at least one ambient variable.

The present disclosure provides a method for adjusting the operation of an internal combustion engine comprising: determining a gradient of an overrun-air line based on an ambient condition and a current operating point; determining a value for a cylinder air mass situated in a cylinder after closure of the gas exchange valves; and using the determined cylinder air mass to adjust one or more operating parameters of the internal combustion engine. The overrun-air line may correspond to an air mass situated in the respective cylinder after closure of the gas exchange valves at predefined operating temperature for the engine, when the engine is operated briefly without fuel metering and combustion. Determining a cylinder air mass may be based at least in part on the current operating point and the current ambient value of the at least one ambient variable.

In one aspect, a skip fire engine controller is described. The skip fire engine controller includes a skip fire module arranged to determine an operational firing fraction and associated cylinder load for delivering a desired engine output. The skip fire engine controller also includes a firing controller arranged to direct firings in a skip fire manner that delivers the selected operational firing fraction. Various methods, modules, lookup tables and arrangements related to the selection of a suitable operational firing fraction are also described.

A controller for a motor vehicle having an internal combustion engine, and a device for detecting a fire in a fluid conduit, the device having a fluid state sensor for detecting a state variable of a fluid that is conducted in the fluid conduit, are provided. The determination of a fire situation is performed in a manner dependent on a signal of the fluid state sensor.

A controller for a motor vehicle having an internal combustion engine, and a device for detecting a fire in a fluid conduit, the device having a fluid state sensor for detecting a state variable of a fluid that is conducted in the fluid conduit, are provided. The determination of a fire situation is performed in a manner dependent on a signal of the fluid state sensor.