An Investigation Of The Different Diffuser Positions Effect On Vehicle Aerodynamic Performance

Abstract

Reducing fuel consumption, increasing road holding and overcoming air resistance are the main goals in the field of vehicle aerodynamics. Therefore, controlling the lift-ing forces is very important for vehicle stability. Generally, lifting forces are used as low as possible and an additional downforce is required in order to increase road holding. Various vehicle parts have been developed to control the airflow in passen-ger cars. One of them is the rear lower diffuser which is located on the floor of the ve-hicle. In this study, the length value of the base diffuser is kept constant as the base edge, and the effects of the diffuser location position on the lifting and drag force at 60 km/h with angles of 10º, 15º, 20º and 30º are investigated. These effects are also investigated comparatively according to flat-floor geometry. As a result of the study, it is observed that the use of the diffuser reduces the negative effects by changing the lifting force from positive to negative, and it provides a significant advantage in drag force compared to the flat-floor geometry, however, the angle changes do not have a significant effect.

Keywords

• Diffuser
• Diffuser angle
• Aerodynamic
• Lift force
• Drag force

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