Abstract: The disclosure relates to a method for the measurement of relative air humidity in a fresh air induction tube of an internal combustion engine. Here a concentration of oxygen in the fresh air induction tube is measured by an oxygen sensor and a temperature in the fresh air induction tube is determined. The relative air humidity is determined depending on the measured concentration of oxygen and the determined temperature.

Abstract: A system and methods for operating four in-line cylinders with common rail injection is described that comprises operating a first cylinder group without a compression and power stroke injection, but with an exhaust stroke injection while operating a second cylinder group with at least a compression stroke injection. In this way, the unburned fuel injected during the exhaust stroke enriches the exhaust-gas flow and further allows heating of the exhaust aftertreatment system. In one example provided, the first cylinder group is further configured to operate in an exhaust heating mode while also operating in a power generating mode.

Abstract: Embodiments of a particle sensor are provided. In one example, a particle sensor for an exhaust system comprises at least two inlet openings for an exhaust-gas flow of the exhaust system, wherein the inlet openings are of different sizes, and at least two sensor elements, wherein in each case one sensor element is arranged downstream of one inlet opening. In this way, the relative proportion of different-sized particles within the exhaust-gas flow may be determined.

Abstract: A method for determining a degree of aging of an oxidizing catalytic converter in an exhaust system of an internal combustion engine is provided. The method comprises generating a temporary increase in carbon monoxide levels in an exhaust gas stream, monitoring subsequent oxidizing action and determining a degree of aging of the oxidizing catalytic converter as a function of the measured oxidizing action. The method further comprises measuring a temperature rise during oxidation and correlating the aging of the converter to the speed of temperature rise.

Abstract: Systems and methods for reducing NOx emissions are provided, comprising: adjusting an amount of water injected into an intake manifold responsive to an oxygen concentration, temperature and pressure in the intake manifold; and heating the injected water if humidity is higher than a threshold. Water injected into the intake manifold decreases the temperature of, and dilutes the oxygen content of intake gases thereby decreasing NOx emissions.

Abstract: The disclosure relates to a system and method for identifying whether a difference between measured lambda and computed lambda, based on mass air flow and mass fuel flow, is due to a drift in fuel metering or a drift in air metering. The determination is based on also measuring exhaust gas NOx using a NOx sensor. By comparing the measured NOx to modeled NOx, drift can be attributed appropriately to the air flow measurement and/or the fuel flow measurement. Appropriate correction in the calibration can be undertaken to overcome sensor drift and/or drift in the fuel injector/fuel system flow characteristics.

Abstract: The systems and methods herein relate the operation of a particle filter which is arranged in an exhaust-gas path of an internal combustion engine, to a device for exhaust-gas aftertreatment which can be operated in accordance with the method that comprises determining a mass flow rate of an exhaust-gas flow flowing in the exhaust-gas path; and supplying ambient air into the exhaust-gas path as a function of the determined mass flow rate. By this method, the spontaneous regeneration of a particle filter within the exhaust system may be abated.

Abstract: An internal combustion engine has a cylinder and an exhaust-gas turbocharger comprising a compressor arranged in an intake system and a turbine arranged in an exhaust-gas discharge system. Various lines are provided for conducting gases including 1) a bypass line branching off from the inlet system downstream of the compressor so as to form an inlet-side junction, and 2) a recirculation line branching off from the exhaust-gas discharge system upstream of the turbine so as to form an outlet-side junction which opens into the bypass line. A first control element at the outlet-side junction adjusts an exhaust-gas quantity conducted through the recirculation line. A second control element at the inlet-side junction has a first position that separates the bypass line from the cylinder and connects the intake line to the cylinder, and a second position that separates the intake line from the cylinder and connects the bypass line to the cylinder.

Abstract: The present disclosure describes systems and methods for recharging a storage catalyst of an internal combustion engine. A method is described, comprising: while operating an engine in a substoichiometric operating mode when the engine is under medium load and responsive to an LNT condition, assisting the engine with an electric machine connected to an engine crankshaft. The electric machine provides an auxiliary drive to assist the engine in maintaining the substantially steady state substoichiometric operating mode which may be used to reduce NOx or SOx build up in a storage catalytic convertor or to assay the condition of a storage catalytic convertor.

Abstract: The present disclosure relates to an exhaust-gas aftertreatment system for an internal combustion engine, having an exhaust line and having provided therein a filter arrangement which comprises a first particle filter element and a second particle filter element, wherein the first particle filter element is equipped with an active regeneration device for restoring its filtration performance. The disclosure furthermore relates to a method for operating an exhaust-gas aftertreatment system of said type and to the use thereof.

Abstract: A system is disclosed herein for a four-stroke internal combustion engine, the system comprising: at least two cylinders; a fuel direct injection device; a variable valve timing system; an engine controller to control spark ignition and valve timing according to load; wherein, below a lower load threshold, a first cylinder is deactivated, an injection of fuel takes place into a combustion chamber of the first cylinder and an outlet valve of the first cylinder is open during a compression stroke. Fuel injected into the deactivated cylinders may enter the exhaust tract through the open outlet valves and serve as a reducing agent therein.

Abstract: An internal combustion engine comprising a turbocharger wherein a bypass line in an exhaust gas discharge system delivers an aqueous urea reductant to an at least one SCR catalyst and a method to maintain the reductant at a desired temperature to maximize its conversion to ammonia and optimize the reduction of NOx in the SCR.

Abstract: A system and method for controlling temperature of a urea reductant to form ammonia for NOx reduction in a selective catalytic reducer coupled to a turbocharged engine exhaust by portioning a flow across the reductant between compressed air and ambient air.

Abstract: Embodiments for heating a catalyst are provided. In one example, a method for controlling an internal combustion engine having an exhaust-gas aftertreatment device during a cold-start phase comprises adjusting a temperature of cooling water to a setpoint operating temperature as a function of a degree of aging of the exhaust-gas aftertreatment device of the internal combustion engine, wherein the temperature of the cooling water is increased more quickly as a present degree of aging of the exhaust-gas aftertreatment device increases.

Abstract: A method for enriching the exhaust gas of an internal combustion engine with a reducing agent is provided, the internal combustion engine including at least one cylinder and having an intake system for admission of charge air, an exhaust gas discharge system for discharging exhaust gases, and at least one exhaust gas aftertreatment system for reducing nitrogen oxides arranged in the exhaust gas discharge system and which is periodically provided with a supply of reducing agent. The method comprises enriching the exhaust gas with the reducing agent in the exhaust gas discharge system upstream of at least the one exhaust gas aftertreatment system when a fuel supply of the at least one cylinder of the internal combustion engine is deactivated due to an absence of load demand.

Abstract: A method for controlling an exhaust gas aftertreatment device of a vehicle hybrid drive is provided. The method comprises operating the hybrid drive only by a combustion engine, only by a non-combustion motor, or by both, as a function of a temperature of the exhaust aftertreatment device, and conducting exhaust gas of the hybrid drive at least partially through the exhaust aftertreatment device, the engine and motor each providing output to power the vehicle. In this way, the aftertreatment device may be operated at an optimal temperature for conversion performance.

Abstract: In one embodiment, a ducting system comprises a feed duct for feeding air and exhaust gases to an internal combustion engine, a discharge duct for discharging the exhaust gases produced by the internal combustion engine from the internal combustion engine, in which one or more exhaust gas aftertreatment units are arranged for aftertreatment of the exhaust gases, and a heating device arranged in the feed duct. The heating device is configured to perform a heating process for preheating the air that is fed to the internal combustion engine. A duration of the heating process and/or heat output given off by the heating device is controlled as a function of a variable approximately representing a state of ageing of at least one of the one or more exhaust gas treatment units.

Abstract: A system is disclosed for a four-stroke internal combustion engine comprising: at least two cylinders; a fuel direct injection device; a variable valve timing system; an engine controller to control valve timing according to load; wherein, below a lower load threshold, a first cylinder is deactivated, an injection of fuel takes place into a combustion chamber of the first cylinder and an inlet valve of the first cylinder is open during a compression stroke. The opening of the inlet valve during a compression stroke of the first cylinder when deactivated allows the substantially homogenous air-fuel mixture therein to escape into the intake manifold and be made available to the second and active cylinder.

Abstract: Embodiments of a particle sensor are provided. In one example, a particle sensor for an exhaust system comprises at least two inlet openings for an exhaust-gas flow of the exhaust system, wherein the inlet openings are of different sizes, and at least two sensor elements, wherein in each case one sensor element is arranged downstream of one inlet opening. In this way, the relative proportion of different-sized particles within the exhaust-gas flow may be determined.

Abstract: The invention relates to a method for protecting a DPF in the exhaust section of an internal combustion engine of a motor vehicle from unintentional combustion of soot in the DPF. According to the invention, the motor vehicle is a hybrid vehicle having at least one electric machine and is able to be driven exclusively by one or more electric machine(s) for some time. The vehicle is operated in a DPF protection mode if the system detects that unintentional combustion of soot is taking place or threatening to take place in the DPF, initiating an automatic decoupling of the combustion engine from the wheel drive train, forward propulsion demands by the driver are met exclusively with the aid of the one or more electric machine(s), and the combustion engine is switched off completely or is operated with stable stoichiometric combustion.