This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Uncertainty Quantification of Motorcycle Racing Upstream Flow Conditions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 14, 2020 by SAE International in United States
Annotation ability available
The upstream flow conditions and the use of tractive power to accelerate a vehicle are both sources of energy loss. The vehicle speed and the upstream flow conditions result in the oncoming wind vector experienced by the moving vehicle. The aim of the present work is to show a new approach to consider the chaotic and random behavior of surrounding flow conditions and their influence on driving performance. The approach is shown for the example of motorbike racing conditions. Special interest was put on a description of the flow conditions with respect to well know turbulent flow field parameters like the turbulent length scale or the turbulence intensity. Depending on where the flow conditions are measured, stationary in the earth reference frame, or on a moving vehicle, it is quite difficult to get a robust description of the flow field parameters. These parameters are used together with the Reynolds number to predict the aerodynamic behavior by correlation functions or maps. Aerodynamic characteristics of vehicles are typically determined in wind tunnels or through numerical simulation for specific flow conditions. As the determination of all these dependencies is difficult for complex shapes the presented approach uses stochastic sensitivity analysis to quantify the influence of the upstream flow condition uncertainties. The test case for this is a generic multi-body model of a motorbike which is accelerating and driving through different environmental flow conditions. The time and the speed at defined observation points are used to quantify the influence of the upstream flow conditions.
CitationFeichtinger, C. and Fischer, P., "Uncertainty Quantification of Motorcycle Racing Upstream Flow Conditions," SAE Technical Paper 2020-01-0667, 2020, https://doi.org/10.4271/2020-01-0667.
- Batchelor , G.K. The Theory of Homogeneous Turbulence Cambridge University Press 1953 7 0-521-04117-1
- Drela , M. Flight Vehicle Aerodynamics The MIT Press 2014 149 978-0-262-52644-9
- Hirschberg , W. May 13, 2009
- Wordley , S. and Saunders , J. On-road Turbulence SAE Int. J. Passeng. Cars - Mech. Syst. 1 1 341 360 2009 https://doi.org/10.4271/2008-01-0475
- Limebeer , D.J.N. and Massaro , M. Dynamics and Optimal Control of Road Vehicles 2018 415 417 978-0-882571-5
- Cocco , G. Motorcycle Design and Technology 2013 133 135 88-7911-344-1
- Van Dijck , T. Computational Evaluation of Aerodynamic Forces on a Racing Motorcycle during High Speed Cornering SAE Technical Paper 2015-01-0097 2015 2015 https://doi.org/10.4271/2015-01-0097
- Cossalter , V. Motorcycle Dynamics Second 2006 213 978-1-4303-0861-4
- Bearman , R.W. Some Effects of Free-Stream Turbulence and the Presence of the Ground on the Flow around Bluff Bodies Aerodynamic Drag Mechanisms of Bluff Bodies and Road Vehicles 978-1-14684-8436-6 1976 95 127
- Cooper , R.K. and Watkins , S. The Unsteady Wind Environment of Road Vehicles, Part One: A Review of the On-Road Turbulent Wind Environment SAE Technical Paper 2007-01-1236 2007 https://doi.org/10.4271/2007-01-1236
- Cooper , R.K. Atmospheric Turbulence with Respect to Moving Ground Vehicles Journal of Wind Engineering and Industrial Aerodynamics 17 215 238 1984 10.1016/0167-6105(84)90057-6
- Schütz , T. and Grün , N. Hucho - Aerodynamik des Automobils Sixth Springer Vieweg 2013 751 743 0.1007/978-3-8348-2316-8
- Newnham , P.S. 2007
- Cogotti , A. Update on the Pininfarina Turbulence Generation System and its effects on the Car Aerodynamics and Aeroacoustics SAE Technical Paper 2004-01-0807 2004 https://doi.org/10.4271/2004-01-0807
- Official MotoGP Homepage https://www.motogp.com/ Jan. 19, 2020
- Leuschen , J. Effect of Ambient Conditions on the Measured Top Speed of a Winston Cup Car SAE Technical Paper 2004-01-3507 2004 https://doi.org/10.4271/2004-01-3507