Patent ID: 8205606

Claim:
An internal combustion engine comprising: an exhaust system which conveys exhaust gas created in engine combustion chambers to atmosphere and which comprises an exhaust manifold through which exhaust gas from the combustion chambers enters the exhaust system, an after-treatment device for treating exhaust gas before passing into the atmosphere, and a sensor providing data for temperature of exhaust gas entering the after-treatment device; and a processor comprising an algorithm that models temperature of exhaust gas at the exhaust manifold as a function of the data from the sensor and other data, including certain thermodynamic constants, certain geometry of the exhaust system, and certain variables related to operation of the engine, and that when executed, processes the data from the sensor and the other data to calculate temperature of exhaust gas at the exhaust manifold, in which the after-treatment device comprises a diesel oxidation catalyst and in which the algorithm comprises a first heat-loss model for modeling heat lost from exhaust gas during passage of exhaust gas from the exhaust manifold through a turbine of a turbocharger and a second heat-loss model for modeling heat lost from exhaust gas during passage through a pipe from the turbine to the diesel oxidation catalyst, and the algorithm, when executed, uses the heat-loss models to calculate a data value for temperature that is added to a data value for temperature from the sensor to calculate temperature of exhaust gas at the exhaust manifold.