## 4 Conclusions  
The numerical WLTC simulation using the AVL CruiseTM software was conducted for a Nissan Qashqai J10 passenger car equipped with a 1.6 L spark-ignition engine operating on pure gasoline (G100) or dual fuel (D-F) consisting of 95% (by mass) gasoline and 5% hydrogen (G95H5). Real vehicle data, fuel properties, and engine experimental research data (fuel consumption, CO, HC, and NO\({}_{x}\) emissions maps) were utilized for the WLTC simulation. Through numerical simulation, the indicators of fuel consumption and pollutant emissions were determined for the vehicle operating under four driving modes: urban cycle (I), medium speed (II), high speed (III), and very high speed (IV).  
1. The addition of 5% hydrogen reduced overall fuel mass consumption by about 10% (primarily due to a higher LHV and a roughly 2.57% increase in thermal efficiency).
2. CO and HC emissions decreased significantly (up to 23.9% and 37.1%, respectively, depending on the driving mode), owing to faster combustion and better efficiency. However, NO\({}_{x}\) emissions increased (by 19.7% in mode IV and by 25.9% in mode II) due to higher combustion temperatures and more intense heat release. Reduced carbon content (by 5%) and lower fuel consumption cut CO\({}_{2}\) emissions by 14.9% compared to pure gasoline. Despite this reduction, the WLTC simulation showed CO\({}_{2}\) levels remain above the EU's 95 g/km target.  
Figure 18: Instant and total CO\({}_{2}\) emissions during the WLTC test: I—Urban cycle; II—Medium-speed cycle; III—High-speed cycle; IV—Very high-speed cycle.  
Blending gasoline with biofuels (e.g., bioethanol, biobutanol) and/or increasing hydrogen concentration in the fuel are potential pathways to further emission reductions and compliance with stricter EU standards.  
To meet EU emission standards, further research is planned, focusing on the use of gasoline and biofuel blends (such as bioethanol, biobutanol, etc.) and increasing the hydrogen concentration in dual fuels.  
Conceptualization, S.P. and A.R.; methodology, A.R. and G.M.; software, T.V. and A.U.; validation, T.V., A.U. and G.M.; formal analysis, S.S. and R.J.; investigation, A.R., T.V. and G.M.; resources, J.Z., A.U., V.M. and V.Z.; data curation, T.V., V.Z. and A.N.; writing--original draft preparation, A.R. and T.V.; writing--review and editing, D.K. and S.S.; visualization, A.R., V.M. and T.V.; supervision, A.R.; project administration, S.P. All authors have read and agreed to the published version of the manuscript.  
Research was conducted as part of the execution of Project \"Mission-driven Implementation of Science and Innovation Programmes\" (No. 02-002-P-0001), funded by the Economic Revitalization and Resilience Enhancement Plan \"New Generation Lithuania\".  
Not applicable.  
The data presented in this study are available on request from the corresponding author.  
A part of the results included in this study have been obtained using internal engine simulation software AVL Cruise(tm) acquired by signing a Cooperation Agreement between AVL Advanced Simulation Technologies and the Faculty of Transport Engineering of Vilnius Gediminas Technical University.  
The authors declare no conflicts of interest.