Aerodynamic interaction mechanisms relevant to the underbodies of Formula 1 cars

Abstract

This thesis presents an investigation of the flow physics governing aerodynamic inter-action mechanisms relevant to Formula One racing cars, in particular the influence of the front wing on the car chassis flat underbody and diffuser. The research has taken a fundamental approach, with emphasis on identifying the fundamental mechanisms governing the interaction. Wake diagnostic techniques have been used to identify the major flow features of the front wing wake that are likely to influence the flat underbody and diffuser. Models have then been designed to simulate these various flow features. A simple model was produced with an underbody which is flat apart from a diffuser over the rear 20% of its length. This was used to simulate the basic flow features of the flat underbody and diffuser of a Formula One car. Wind tunnel measurements of force and surface pressure have been made on this diffuser model with the various upstream models simulating aspects of the front wing wake. It has been found that the downforce generated by the diffuser model is highly sensitive to the configuration of the upstream front wing. Although, for the majority of front wing configurations the downforce generated by the diffuser model was reduced, it was discovered that for certain arrangements the downforce may actually be enhanced. By piecing together the various results gathered over the course of the research, the underlying flow physics involved in the interaction have been identified. Using this information, suggestions are made for how the configuration of the front wing may be optimised for minimum negative impact on the performance of the car underbody and diffuser.