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Aerodynamic Optimization of Vehicle Configuration Based on Adjoint Method
Technical Paper
2020-01-0915
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Due to the increasingly stringent environmental regulations all around the world confronted by exhaust emission and energy consumption, improving fuel economy has been the top priority for most automotive manufacturers. In this context, the basic process for vehicle shape development has evolved into optimizing the design to achieve better aerodynamic characteristics, especially drag reduction. Of all the optimization approaches, the gradient-based adjoint method has currently received extensive attention for its high efficiency in calculating the objective sensitivity with respect to geometry parameters, which is the first and foremost step for subsequent shape modification.
In this work, the main goal is to explore the adjoint method through optimizing the vehicle shape for a lower drag based on a production SUV. Firstly, the influence of different mesh schemes was discussed on sensitivity prediction of aerodynamic drag. Secondly, according to the sensitivity distribution, several key areas, like the side mirrors, A pillars, air dam, and rear lamps, were respectively altered through mesh morphing process. Furthermore, the optimized effect was validated by steady as well as transient simulation. Steady Reynolds Averaged Navier Stokes (RANS) approach was used for the primal flow solution of adjoint calculations, while transient simulation with Stress Blended Eddy Simulation (SBES) was also performed on the baseline and the optimized vehicle for more detailed flow field structure. The overall drag reduction is approximately 8counts for steady result, and 10counts for unsteady solution. Finally, the drag reduction effect of the optimized side mirrors and air dam was correlated with full-scale wind tunnel test.
This paper evaluates the effectiveness of adjoint method for aerodynamic optimization of a production vehicle, which indicates more extensive and promising application of this approach in the early stage of vehicle development for its high efficiency as well as strong robustness.
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Ren, C., Zhou, H., Wu, H., Chen, Q. et al., "Aerodynamic Optimization of Vehicle Configuration Based on Adjoint Method," SAE Technical Paper 2020-01-0915, 2020, https://doi.org/10.4271/2020-01-0915.Data Sets - Support Documents
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References
- Fang , T. The Uniform Design: Application of Number-Theoretic Methods in Experimental Design Acta Math. Appl. Sinica 3 363 372 1980
- Saad , Y. and Schultz , M. GMRES: A Generalized Minimal Residual Algorithm for Solving Non-symmetric Linear Systems SIAM J. Sci. Stat. Comput. 7 3 856 869 1986
- Cogotti , A. A Parametric Study on the Ground Effect of a Simplified Car Model SAE Technical Paper 980031 1998 https://doi.org/10.4271/980031
- Othmer , C. and Grahs , T. Approaches to Fluid Dynamic Optimization in the Car Development Process Proceedings of the EUROGEN Conference Munich, Germany 2005
- Giles , M.B. and Pierce , N.A. An Introduction to the Adjoint Approach to Design Flow, Turbulence and Combustion 65 3-4 393 415 2000 10.1023/A:1011430410075
- Papadimitriou , I. and Giannakoglou , C. Aerodynamic Shape Optimization Using First and Second Order Adjoint and Direct Approaches Archives of Computational Methods in Engineering 15 4 447 488 2008 10.1007/s11831-008-9025-y
- Han , T. , Hill , C. , and Jindal , S. Adjoint Method for Aerodynamic Shape Improvement in Comparison with Surface Pressure Gradient Method SAE Int. J. Passeng. Cars - Mech. Syst. 4 1 100 107 2011 https://doi.org/10.4271/2011-01-0151
- Hill , C. The Automatic Generation of Adjoint Solutions for a General-Purpose Flow Solver 46th AIAA Aerospace Sciences Meeting and Exhibit 2008 Reno, NV
- Zhang , Y. , Li , J. , Xu , C. , and Zhu , Z. Vehicle Aerodynamic Optimization: On a Combination of Adjoint Method and Efficient Global Optimization Algorithm SAE Int. J. Passeng. Cars-Mech. Syst. 12 2 139 153 2019 10.4271/06-12-02-0011
- Pironneau , O. On optimum design in fluid mechanics Journal of Fluid Mechanics 64 97 110 1974
- Löhner , R. , Soto , O. , and Yang , C. 2003
- Helgason , E. and Krajnovic , S. Aerodynamic Shape Optimization of a Pipe using the Adjoint Method Proceedings of the ASME 2012 International Mechanical Engineering Congress & Exposition (IMECE) Houston, TX 2012
- Jakubek , D. and Wagner , C. Shape Optimization of Train Head Cars using Adjoint-Based Computational Fluid Dynamics Proceedings of the First International Conference on Railway Technology Las Palmas de Gran Canaria, Spain 2012
- Othmer , C. Adjoint Methods for Car Aerodynamics Journal of Mathematics in Industry 4 6 2014 10.1186/2190-5983-4-6
- Blacha , T. , Gregersen , M. , Islam , M. , and Bensler , H. Application of the Adjoint Method for Vehicle Aerodynamic Optimization SAE Technical Paper 2016-01-1615 2016 https://doi.org/10.4271/2016-01-1615
- Francesconi lng , G. , Miretti , L. , Lorefice , L. , Pitillo lng , F. et al. Application of Adjoint Methods on Drag Reduction of Current Production Cars SAE Technical Paper 2018-37-0016 2018 https://doi.org/10.4271/2018-37-0016
- Han , T. , Kaushik , S. , Karbon , K. , Leroy , B. et al. Adjoint-Driven Aerodynamic Shape Optimization Based on a Combination of Steady State and Transient Flow Solutions SAE Int. J. Passeng. Cars - Mech. Syst. 9 2 695 709 2016 https://doi.org/10.4271/2016-01-1599
- Magazoni , F. , Buscariolo , F. , Maruyama , F. , Alves , J. et al. Aerodynamic Shape Improvement for Driver Side View Mirror of Hatchback Vehicle using Adjoint Optimization Method SAE Technical Paper 2015-36-0156 2015 https://doi.org/10.4271/2015-36-0156
- 2015
- Menter , R. , Matyushenko , A. , and Lechner , R. Development of a Generalized k-ω Two-Equation Turbulence Model Numerical Fluid Mechanics and Multidisciplinary Design 142 2018
- Buscariolo , F. , Magazoni , F. , Wolf , M. , Maruyama , F. et al. Analysis of Turbulence Models Applied to CFD Drag Simulations of a Small Hatchback Vehicle SAE Technical Paper 2016-36-0201 2016 https://doi.org/10.4271/2016-36-0201
- Islam , M. , Decker , F. , de Villiers , E. , Jackson , A. et al. Application of Detached-Eddy Simulation for Automotive Aerodynamics Development SAE Technical Paper 2009-01-0333 2009 https://doi.org/10.4271/2009-01-0333
- Heft , I. , Indinger , T. and Adams , A. Investigation of Unsteady Flow Structures in the Wake of a Realistic Generic Car Model 29th AIAA Applied Aerodynamics Conference 2011 Honolulu, HI
- Menter , R. A New Paradigm in Hybrid RANS-LES Modeling Proceedings of the 6th Symposium on Hybrid RANS-LES Methods 2016
- Strangfeld , C. , Wieser , D. , Schmidt , H. , Woszidlo , R. et al. Experimental Study of Baseline Flow Characteristics for the Realistic Car Model DrivAer SAE Technical Paper 2013-01-1251 2013 https://doi.org/10.4271/2013-01-1251
- Mack , S. , Indinger , T. , Adams , N. , and Unterlechner , P. The Ground Simulation Upgrade of the Large Wind Tunnel at the Technische Universität München SAE Technical Paper 2012-01-0299 2012 https://doi.org/10.4271/2012-01-0299