<p>Platooning represents a crucial strategy for mitigating emissions from heavy-duty vehicles (HDVs). This study evaluates the effects of platoon composition on the surrounding airflow utilizing a computational fluid dynamics (CFD) model, and quantifies the resultant fuel efficiency and CO₂ emissions. This study examines fuel consumption data reconstructed from field experiments to validate the CFD model’s ability to accurately simulate drag forces within a homogeneous three-truck platoon. The potential for fuel savings was assessed based on CFD-simulated fuel consumption, taking into account various inter-vehicle distances and driving speeds. The model successfully reproduced the fuel consumption observed in a platooning formation comprising lead, middle, and trailing trucks, with an error margin below 6.2%. Fuel consumption analysis shows that while lead and middle trucks consume more fuel with increased inter-vehicle distances, the trailing truck's consumption decreases at specific distance-to-length ratios (D/L), increasing again beyond a D/L of 1.1. Additionally, a significant decrease in total fuel efficiency was noted for D/L ratios exceeding 1.5. Considering the diverse platooning scenarios analyzed, the study anticipates an annual reduction of up to 7 tons of CO₂ equivalent per vehicle. By optimizing platooning configurations, this research contributes to enhancing fuel efficiency and reducing emissions from HDVs.</p>