The evaluation of NOx emissions in RDE tests including dynamic driving conditions

Nowadays, one of the most critical roles of both legislators and society itself is to look after the future of our environment. There are many reasons for the deterioration of air quality. Unfortunately, pollution from the automotive sector is still widely regarded as one of them. For this reason, the European Commission has been improving testing procedures for years, including more and more advanced measurement capabilities and extending testing to include further exhaust gas compounds. The object of the article is to assess the actual emission of nitrogen oxides (NOx) from two passenger cars equipped with gasoline engines. The authors carried out the tests according to the guidelines of the Real Driving Emissions (RDE) test procedure with the use of PEMS (Portable Emissions Measurements System) mobile measuring equipment. The influence of dynamic conditions (such as vehicle speed, acceleration and product of vehicle speed and acceleration) during the tests on NOx emissions was determined and the areas in which this relation was the most visible were estimated.