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Emergency Braking Dynamics of Ground Effects Open-Wheeled Racing Cars
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Sector:
Event:
Autotechnologies Conference
Language:
English
Abstract
IN ALL FORMS of racing, driver safety is of paramount concern. This is particularly true in the case of open-wheel, single seat vehicles such as Formula One and Indy cars, for which there is only minimal structural protection surrounding the driver.
In the present work, we analyze the dynamics of emergency braking, with and without the possibility of a spin. Aerodynamic drag and lift are included, and realistic vehicle properties were used to predict deceleration rates and associated vehicle dynamics (e.g., spin rotations>180°). Reduction of ground effects downforce, changes in drag properties due to large changes in vehicle yaw angle of attack and kinetic energy of rotatory masses of the vehicle are discussed. Results include time histories of velocity, vehicle position -v- time trajectories and the associated kinetic energy required to be dissipated by the vehicle structure at various speeds.
Results show that surprisingly large amounts of energy are dissipated through simple aerodynamic losses, and that the amount of kinetic energy remaining to be dissipated after even reasonably short braking maneuvers may be quite manageable from a vehicle design point of view. Finally, suggestions regarding rules modifications and vehicle configuration requirements are developed in light of the results of the simulations.
Authors
Citation
Metz, L., "Emergency Braking Dynamics of Ground Effects Open-Wheeled Racing Cars," SAE Technical Paper 910012, 1991, https://doi.org/10.4271/910012.Also In
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