Authors & Affiliations: Dordea Traian¹, Tudor Camil¹, Melnic Lucia¹, Beldugan Adrian^1*, Ionascu Sorin¹, Stania Lucian¹

¹Ovidius University of Constanta, Faculty of Mechanical, Industrial and Maritime Engineering, Department of Industrial Management and Road Auto-Vehicles, 124 Mamaia Ave., Constanta 900507, Romania

*Corresponding author: beldugan.adrian@gmail.com

Abstract. The aging vehicle fleet in Romania, with an average age of approximately 17 years, is predominantly composed of 1.6L spark ignition (SI) and 1.9L compression ignition (CI) powertrains. However, real-world emission data for medium-sized Romanian cities remain largely unavailable, while standardized test cycles such as WLTP inadequately represent local urban driving conditions. This study addresses this gap through a dual approach: experimental data acquisition and traffic microsimulation. Results show that the real driving cycle for Constanța differs significantly from WLTP in terms of average speed, idle percentage, and acceleration patterns. The study provides the first published driving cycle for Constanța and offers quantitative support for local emission reduction strategies.

Keywords: real driving emissions, spark ignition, compression ignition, driving cycle, OBD-II, SUMO, HBEFA, fleet electrification, urban mobility, Constanța.