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Since 2019 in-service conformity testing for vehicles as described in EU legislation 2018/1832 is active and obliges numerous emission control tests on WLTP and RDE cycles. For the on-road portion of these tests typically Portable Emissions Measurement System (PEMS) are used. While these systems provide all necessary regulated emissions measurements, their use and handling are difficult due to their weight, cumbersome installation, and their limited accessibility due to a high price point. In order to make the real-driving measurement accessible for a maximum number of institutions, IFPEN is developing a compact measurement system with an advanced cloud modeling of the vehicle for more cost-effective and user friendly RDE and ISC testing. This real-time analyzer, named “REAL-e” is developed as an IoT system, who’s measured data is transferred in real-time to a secured cloud service for enhanced data processing and data enrichment.

Meeting Euro 6d NOx emission regulations lower than 80 mg/km for light duty diesel (60 mg/km gasoline) vehicles remains a challenge, especially during cold-start tests at which the selective catalyst reduction (SCR) system does not work because of low exhaust gas temperatures (light-off temperature around 200 °C). While several exhaust aftertreatment system (EATS) designs are suggested in literature, solutions with gaseous ammonia injections seem to be an efficient and cost-effective way to enhance the NOx abatement at low temperature. Compared to standard SCR systems using urea water solution (UWS) injection, gaseous NH3 systems allow an earlier injection, prevent deposit formation and increase the NH3 content density. However non-uniform ammonia mixture distribution upstream of the SCR catalyst remains an issue. These exhaust gas/ NH3 inhomogeneities lead to a non-optimal NOx reduction performance, resulting in higher than expected NOx emissions and/or ammonia slip.

Ever growing traffic has a detrimental effect on health and environment. In response to climate warming and health concerns, governments worldwide enforce more stringent emission standards. NOx emissions limits are some of the most challenging to meet using fuel-efficient lean-burn engines. The Selective Catalytic Reduction (SCR) is one consolidated NOx after-treatment technique using urea water solution (UWS) injection upstream of the catalytic converter. A recent development of SCR, using gaseous ammonia injection, reduces wall deposit formation and improves the cold-start efficiency. The mixing of gaseous ammonia with the exhaust gases is one of the key challenges that need to be overcome, as the effectiveness of the system is strongly dependent on the mixture uniformity at the inlet of the SCR catalyst.