The Aerodynamic Forces Induced on a Passenger Vehicle in Response to a Transient Cross-Wind Gust at a Relative Incidence of 30°

The aerodynamic forces induced on a generic ‘hatchback’ model have been measured as it passes through a perpendicular cross-wind jet generating a relative yaw angle of 30°. This has been done in the unique University of Durham automotive wind tunnel, which utilises the stationary model approach, with the cross-wind being introduced by means of a second jet which is separated from the main jet by a moving belt and aperture assembly. Data acquisition was by means of an array of surface pressure tappings. Transient pressure force and moment coefficients have been measured and it is shown that the side and lift forces experienced in the transient situation exceed the steady state values at corresponding yaw angles by between 10% and 20%.