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Predicting Automobile Aerodynamic Characteristics Using an iterative Viscous/Potential Flow Technique
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Abstract
An iterative viscous/potential flow calculation method is described in this paper. A potential-flow panel method is coupled with integral boundary layer methods. Simple linear doublet sheets are used to enclose the low-energy separated-flow region of the wake. Calculations for various body shapes demonstrate that unseparated flow pressure distributions are accurately calculated. Body lift trends are also properly computed for a simple body with separation only at the base and in close ground proximity. However, the prediction of average base pressure is only partially successful. The base pressures for a limited number of geometries, which include a Porsche 924, are properly predicted, but calculations for other shapes indicate that the separated-flow wake model must be improved for general body shapes.
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Summa, J. and Maskew, B., "Predicting Automobile Aerodynamic Characteristics Using an iterative Viscous/Potential Flow Technique," SAE Technical Paper 830303, 1983, https://doi.org/10.4271/830303.Also In
References
- Morel, T. “The Effect of Base Slant on the Flow Pattern and Drag of Three-Dimensional Bodies with Blunt Ends” Proceedings of Symposium on Aerodynamic Drag Mechanisms of Bluff Bodies and Road vehicles Sovran G. Plenum Press New York 1978 191 226
- Hirt, C.W. Ramshaw, J.W. “Prospects for Numerical Simulation of Bluff-Body Aerodynamics” Aerodynmaic Drag Mechanisms of Bluff Bodies and Road Vehicles Symposium Proceedings 313 355
- Ahmed, S.R. Hucho, W.-H. “The Calculation of the Flow Field Past a Van with the Aid of a Panel Method” Paper No. 770390 , Society of Automotive Engineers, Inc. 1977
- Hess, J.L. Smith, A.M.O. “Calculation of Non-Lifting Potential Flow about Arbitrary Three-Dimensional Bodies” Douglas Aircraft 1962
- “High Angle-of-Attack Aerodynamics” AGARD CP-247 October 1978
- “Computation of Viscous-Inviscid Interactions” AGARD CP 291 October 1980
- Seetharam, H.C. “Experimental Investigation of Separated Flow Fields on an Airfoil at Subsonic Speeds” Ph.D. Dissertation Wichita State University March 1975
- Maskew, B. Dvorak, F.A. “The Prediction of CLMAX Using a Separated Flow Model” J. Amer. Hel. Soc. April 1978
- Young, W.J., Jr. Hoad, D.R. “Comparison of Flow Surveys above Stalled Wings” AIAA Paper No. 79–0147 January 1979
- Gross, L.W. “The Prediction of Two-Dimensional Airfoil Stall Progression” AIAA Paper No. 78–155 January 1978
- Zumwalt, G.W. Naik, S.N. “An Analytical Method for Highly Separated Flow on Airfoils at Low Speeds” Wichita State University Aeronautical May 1977
- Henderson, M.L. “A Solution to the Two-Dimensional Separated Wake Modelling Problem and its Use to Predict CLMAX of Arbitrary Airfoil Sections” AIAA Paper 78–156 January 1978
- Jacob, K. “Advancement of a Method for Calculating Separated Flows around Airfoils with Special Consideration of Profile Drag” April 1977
- Dvorak, F. A. Maskew, B. Woodward, F.A. “Investigation of Three-Dimensional Flow Separation on Fuselage Configurations” U.S. Army USAAMRDL TR-77-4 March 1977
- Maskew, B. Rao, B.M. Dvorak, F.A. “Prediction of Aerodynamic Characteristics for Wings with Extensive Separations” AGARD CP-291 October 1980
- Lamb, Sir H. Hydrodynamics 6th Ed. Dover Publications New York, N., Y. 1945
- Curle, H. “A Two-Parameter Method for Calculating the Two-Dimensional Incompressible Laminar Boundary Layer” J. R. Aero. Soc. 71 1964
- Thwaites, B. “Approximate Calculation of the Laminar Boundary Layer” Aero. Ouart. 1 1949
- Nash, J.F. Hicks, J.G. “An Integral Method Including the Effect of Upstream History on the Turbulent Shear Stress” Proceedings Computation of Turbulent Boundary Layers--1968 AFOSR-IFP Stanford Conference 1 Stanford University Dept. of Mech. Eng. Stanford, California
- Morino, L. Chen, L.-T. Suci, E.O. “Steady and Oscillatory Subsonic and Supersonic Aerodynamics around Complex Configurations” AIAA J. 13 3 March 1975
- Johnson, F.T. Rubbert, P.E. “Advanced Panel-Type Influence Coefficient Methods Applied to Subsonic Flows” AIAA Paper No. 75-50 January 1975
- Bristow, D.R. Grose, G.G. “Modification of the Douglas Neumann Program to Improve the Efficiency of Predicting Component Interference and High Lift Characteristics” NASA CR-3020 1978
- Maskew, B. “Prediction of Subsonic Aerodynamic Characteristics--A Case for Low-Order Panel Methods” Paper 81-0252, Presented at the AIAA 19th Aerospace Sciences Meeting, St. Louis, MO January 12–15 1981
- Yip, L.P. Shubert, G.L. “Pressure Distributions on a 1-by 3 Semispan Wing at Sweep Angles from 0° to 40° in Subsonic Flow” NASA TM-72755 December 1976
- Maskew, B. Rao, B.M. “Calculation of Vortex Flows on Complex Configurations” 13thCongress of the International Council of the Aeronautical Sciences, AIAA Aircraft Systems & Technology Conference 1 Seattle, WA August 1982
- Winklemann, A. E. “Flow Field Surveys of Separated Flow on a Rectangular Planform Wing” Paper 81-0255, Presented at the AIAA 19th Aerospace Sciences Meeting at St. Louis, MO January 1981
- Clark, D.R. Dvorak, F. Maskew, B. Summa, J.M. Woodward, F.A. “Helicopter Flow Field Analysis” USARTL-TR-79-4 1979
- Clark, D.R. Wilson, F. “A Study of the Effect of Aft Fuselage Shape on Helicopter Drag” Presented at the 6th European Rotorcraft and Powered Lift Aircraft Forum, Paper No. 50, Bristol, England September 1980
- Fage, A. “Experiments on a Sphere at Critical Reynolds Numbers” Great Britain Aero. Res. Comm. Tech. Rept. R&M 1766 1937
- Fackrell, J.E. “The Simulation and Prediction of Ground Effect in Car Aerodynamics” Imperial College Aeronautics London, England 1975
- Maull, D.T. “Mechanisms of Two-and Three-Dimensional Base Drag” Proceedings of Symposium on Aerodynamic Drag Mechanisms on Bluff Bodies and Road Vehicles Sovran G. et al. Plenum Press New York 1978 137153
- Ahmed, S.R. Baumert, W. “The Structure of Wake Flow Behind Road Vehicles” Symposium on Aerodynamics of Transportation Vehicles Morel T. et al. ASME New York 1979 93 103
- Burst, H. Srock, R. “Die Karosserie des Porsche 924-Schwerpunkte der Entwicklung” Sonderdruck aus ATZ Automobil-technische Zeitschrift 79 Jahrgang 2u.3 1977
- Seddon, J. “Aerodynamics of the Helicopter Rear Fuselage Upsweep” Proceedings of the Eighth European Rotorcraft Forum, Paper No. 2.12, Aix-en-Provence, France September 1982