Renault S.a.s.

Renalt S.a.s.

Olivier Meurisse

Fabrice Gauvin

Pascal Barrillon

Stephane Cochet

Laurent Leprieur

Emmanuel Poilane

Stephane Bourret

A method and device for estimating temperature of gases arising from internal combustion of an engine at the entrance to a system for post-treatment of the gases. The post-treatment system is downstream from a system for treatment of the gases, which may include a nitrogen oxide NOtrap, an oxidation catalyst, or a 4-way catalyst. The systems connect to each other by a line, wherein the treatment system is considered as the whole of a whole finite number n of fictive elementary reactors Rthat are perfectly agitated and serially connected, wherein the total number n of fictive elementary reactors Ris determined, in particular as a function of volume of the treatment system, and the fictive elementary reactors Rare numbered from 1 to n in the gas flow direction along the treatment system. Fictive elementary reactor Ris the last to be cross-flown by the gases before leaving the treatment system, and the temperature at the post-treatment system entrance downstream from the system for the treatment of the gases is calculated from the temperature inside the last fictive elementary reactor R.

Method and device for estimating the temperature of exhaust gases entering into a post-treatment system arranged downstream from a system for the treatment of said gases

The invention relates to a method of estimating a nitrogen oxide mass stored in a catalytic nitrogen oxide trapping device () which comprises a catalytic phase and which is traversed by the exhaust gases () from the internal combustion engine () of a motor vehicle () comprising an electronic control unit (). The inventive method consists in: discretising the geometry of the catalytic trapping device () into several (n) perfectly-stirred, successive individual reactors (); and combining a thermal model, which can be used to calculate the temperature variation of the catalytic phase of the catalytic trapping device () during the traversing movement of the exhaust gases, and an absorption model, which can be used at any moment to calculate the nitrogen oxide mass stored in the catalytic trapping device () on the basis of the characteristics of said device (), the temperatures from the thermal model for each individual reactor and the exhaust gas mass flow from the engine ().

Method and device for estimating a nitrogen oxide mass stored in a catalytic trapping device of a motor vehicle

A method for diagnosing the operating condition of an internal combustion engine exhaust gas recycling valve. The method acquires a measurement value of a reference position of the recycling valve at a predetermined time corresponding to a normally closed position of the valve, calculates the difference between the acquired reference value and a reference value acquired during a diagnostic cycle previously carried out, and compares the calculated difference with a threshold value for detecting opening of the valve.

Method and device for diagnosing the operating condition of an internal combustion engine exhaust gas recycling valve

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Antony, France

Olivier Meurisse