Mona Lisa M. Oliveira and Nara A. Policarpo and Ana Luiza B. P. Barros and Carla A. Silva
Evaluation of NH3Slip from Diesel Vehicles Equipped with Selective Catalytic Reduction Systems by Neural Networks Approach
323 - 329
2018
12
4
International Journal of Energy and Environmental Engineering
https://publications.waset.org/pdf/10008817
https://publications.waset.org/vol/136
World Academy of Science, Engineering and Technology
Selective catalytic reduction systems for nitrogen oxides reduction by ammonia has been the chosen technology by most of diesel vehicle (i.e. bus and truck) manufacturers in Brazil, as also in Europe. Furthermore, at some conditions, overstoichiometric ammonia availability is also needed that increases the NH3 slips even more. Ammonia (NH3) by this vehicle exhaust aftertreatment system provides a maximum efficiency of NOx removal if a significant amount of NH3 is stored on its catalyst surface. In the other words, the practice shows that slightly less than 100 of the NOx conversion is usually targeted, so that the aqueous urea solution hydrolyzes to NH3 via other species formation, under relatively low temperatures. This paper presents a model based on neural networks integrated with a road vehicle simulator that allows to estimate NH3slip emission factors for different driving conditions and patterns. The proposed model generates high NH3slips which are not also limited in Brazil, but more efforts needed to be made to elucidate the contribution of vehicleemitted NH3 to the urban atmosphere.
Open Science Index 136, 2018