Abstract: Aerodynamic characteristics of a Honda civic car 2009 are of significant interest in reducing car-racing accidents due to wind loading and in reducing the fuel consumption. Even though these vehicles typically have a more rigid chassis and a stiffer suspension to aid in high-speed maneuverability, a spoiler can still be beneficial. In this thesis will focus on CFD-based lift and drag prediction on the car body after the spoiler is mounted at the rear edge of the vehicle, a car rear spoiler is designed and modeled in 3D modeled software CREO by different models of spoilers (NACA 4412& NACA 6409) and analysis done by ANSYS software at different speeds (70, 90 & 110km/hr). In this thesis the CFD analysis to determine the lift force, drag force, mass flow rate, and pressure drop. 3D modeled in parametric software CREO and analysis done in ANSYS.

Keywords: Finite element analysis, spoiler, CFD analysis, drag force and lift force.