Numerical Analysis of Rear Spoilers in Improving Vehicle Traction

The vehicle aerodynamics is significantly influenced by its front shape covering hood, bumper, rounds and tapers. Similarly, vehicle rear geometry also influences its aerodynamics which includes trunks and spoilers. With high standards of road safety regulations, the use of aerodynamics can significantly improve vehicle stability especially at high speeds and at turning. The optimized design of spoilers inspired by aircraft wings can significantly increase negative lift and thus improve traction which gives stable and controllable drive at high speeds. The current research investigates the application of NACA inspired rear spoiler in passenger sedan cars using computational fluid dynamics. The CAD model of car is established in Creo project package and analyzed using ANSYS CFX 18.1 software package. The CFD analysis is conducted at four different air speeds (15.5, 25.5, 35.5 and 45.5 m/s) using standard k-epsilon turbulence model. The study shows that the application of spoilers significantly increased vehicle traction while minimal increase in drag force and power consumption. With increase in vehicle velocity the percentage increase in negative lift rises except at 35.5 m/s and with the increase in negative lift the traction rises and thus helps avoiding skidding of vehicles at high speeds or at sharp turns.