Abstract: The present invention is an on-board vehicle emissions measurement system. The system comprises at least one sensor (CAP) downstream from the aftertreatment system, and optionally a sensor plugged into the vehicle diagnostics port, and a computer (SIN) including models (MOD VEH, MOD MOD, MOD POT). According to the invention, emissions determination is based on the signal from sensor (CAP) and on models (MOD VEH, MOD MOT, MOD POT).

Abstract: The present invention is a method of determining emissions of vehicle pollutants using an on-board measurement system with a sensor (CAP) and a computer system including a generic model (MOD GEN) of the vehicle. The method is based on the use of the measurements and of the model for determining the amount of pollutants.

Abstract: The present invention is an on-board vehicle emissions measurement system. The system comprises at least one sensor (CAP) downstream from the aftertreatment system, and optionally a sensor plugged into the vehicle diagnostics port, and a computer (SIN) including models (MOD VEH, MOD MOD, MOD POT). According to the invention, emissions determination is based on the signal from sensor (CAP) and on models (MOD VEH, MOD MOT, MOD POT).

Abstract: A method of detecting nitrogen compound emissions in exhaust gases treated with selective catalytic reduction achieved by injecting a reducing agent into the gases and by passing these gases through a catalyst include sending the signal collected by a gas detector arranged in the exhaust gas downstream from the catalyst and representative of the amount of NOx (NOxsonde) at the catalyst outlet to a computing unit, decomposing this signal into a value representative of the effective NOx amount (NOxréel) at the outlet of catalyst established by the SCR catalyst model, into a detector perturbation coefficient (k) and into a value representative of the ammonia amount (NH3réel) via an integrated model so as to obtain NOxsonde=NOxréel+k.NH3réel, evaluating coefficient (k) from this decomposition, and determining the presence of nitrogen compounds downstream from the catalyst when coefficient (k) is greater than or equal to 1.

Abstract: The present invention is a process for treating pollutants present in exhaust gases moving in an exhaust line (22) and originating from the combustion in at least one cylinder (12) of an internal combustion engine (10), which is, in particular, a motor vehicle. The line comprises at least one selective catalytic reduction catalyst (30) for the treatment of the nitrogen oxides (NOx) present in these gases and at least one injector (28) of a reducing agent. According to the invention, the process forms ammonium nitrate in the catalyst (30), and decomposes the ammonium nitrate by contributing external energy for exhaust gas temperatures of less than approximately 200° C. and a hydrocarbon is used to increase the sensitivity of the ammonium nitrate, so as to obtain a highly exothermic decomposition of this nitrate.

Abstract: A method of detecting nitrogen compound emissions in exhaust gases treated with selective catalytic reduction achieved by injecting a reducing agent into the gases and by passing these gases through a catalyst include sending the signal collected by a gas detector arranged in the exhaust gas downstream from the catalyst and representative of the amount of NOx (NOxsonde) at the catalyst outlet to a computing unit, decomposing this signal into a value representative of the effective NOx amount (NOxréel) at the outlet of catalyst established by the SCR catalyst model, into a detector perturbation coefficient (k) and into a value representative of the ammonia amount (NH3réel) via an integrated model so as to obtain NOxsonde=NOxréel+k.NH3réel, evaluating coefficient (k) from this decomposition, and determining the presence of nitrogen compounds downstream from the catalyst when coefficient (k) is greater than or equal to 1.

Abstract: A method of detecting nitrogen compound emissions in exhaust gases treated with selective catalytic reduction achieved by injecting a reducing agent into the gases and by passing these gases through a catalyst include sending the signal collected by a gas detector arranged in the exhaust gas downstream from the catalyst and representative of the amount of NOx (NOxsonde) at the catalyst outlet to a computing unit, decomposing this signal into a value representative of the effective NOx amount (NOxréel) at the outlet of catalyst established by the SCR catalyst model, into a detector perturbation coefficient (k) and into a value representative of the ammonia amount (NH3réel) via an integrated model so as to obtain NOxsonde=NOxréel+k.NH3réel, evaluating coefficient (k) from this decomposition, and determining the presence of nitrogen compounds downstream from catalyst (16) when coefficient (k) is greater than or equal to 1.