DESIGN OF AERODYNAMIC PARTS TO REDUCE DRAG COEFFICIENT OF A PASSENGER VAN

Air resistance plays a significant role in vehicle energy consumption. Commercial passenger vans with 7 - 12 seats are widely used for public transportation across Thailand. Most passenger vans were designed in near-rectangular shapes to maximize cabin space, which is considered poor aerodynamic efficiency and results in high fuel consumption at cruising speed. This research focused on finding suitable aerodynamic parts to reduce air resistance on such vans. The most popular van model was used as a basis for the study. It has a drag coefficient of 0.36. Effects of various aerodynamic parts on the drag coefficient reduction were studied computationally at 90 kilometers per hour wind velocity using SolidWorks Flow Simulation software. The results showed that a rear roof spoiler is the most effective aerodynamic part. Upon optimizing the spoiler geometry, the drag coefficient is reduced to 0.32. This resulted in an 5.63% reduction in fuel consumption.