Abstract
New index “NOx emission (g) per CO2 1 kg” is calculated by data of NOx and CO2 emission measured with using the sensor-based emission measurement system (SEMS) consisting of a NOx sensor, a digital tachograph and a gas flow meter. And then we proposed a method to monitor NOx purification performance at road driving with using the above-mentioned index and exhaust-gas temperature. Moreover, we applied this method to a deterioration diagnosis for a urea selective catalytic reduction (SCR) system. As a result of consideration based on deterioration case, it was indicated that this method is effective for the diagnosis.
