Optimizing diesel vehicle aerodynamics for energy efficiency of Garnesa: Aligning engineering innovation with SDG 7

¹ Department of Mechanical Engineering, State University of Surabaya, Ketintang Street, 60231, Surabaya, Indonesia
² Department of Mechanical Engineering, National Cheng Kung University, Zi-Chiang Campus, No.1, University Road, Tainan City 70101, Taiwan (R.O.C.)

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Abstract

This study investigates aerodynamic optimization strategies for a Garnesa diesel vehicle using Computational Fluid Dynamics (CFD) to enhance energy efficiency and support Sustainable Development Goal 7 (Affordable and Clean Energy). A virtual three-dimensional wind tunnel was used to examine drag and lift characteristics at inlet velocities between 20 km/h and 65 km/h. The findings reveal that both the drag coefficient (C_d) and lift coefficient (C_L) increase linearly with vehicle speed, confirming that aerodynamic forces are strongly dependent on operating velocity. Geometric modifications such as a smoother roof taper, a sharper rear profile, and a deeper diffuser significantly improved the aerodynamic performance of the optimized model, resulting in a drag reduction of up to 33.33%, and an average lift reduction of approximately 9.61% compared with the baseline configuration. These enhancements improve aerodynamic stability, lower pressure drag, and reduce energy losses, which in turn contribute to better vehicle handling. Overall, the results demonstrate that carefully designed aerodynamic modifications can substantially increase energy efficiency without changes to the powertrain and support sustainable mobility initiatives aligned with SDG 7.