Numerical and Experimental Enhancement of the Aerodynamic Performance of a Road Vehicle using Passive Flow Control

Document Type : Regular Article


Nigde Vocational School of Technical Sciences, Nigde Omer Halisdemir University, Nigde, 51100, Turkey



This study focused on reducing the drag force of a road vehicle using passive flow control. The aerodynamic performance of the model vehicle was improved by applying originally designed vortex generators. The drawing data of the model vehicle and vortex generators were designed in the Solid Works® program. The drag force measurements and flow visualizations were performed in the Fluent® program with the Reynolds numbers in the range of 2.8×105-6.6×105. Accordingly, the CD value of the base model vehicle decreased by 6.22%, 4.59%, 3.38%, and 3.04%, respectively, using the originally designed vortex generator. This aerodynamic improvement rate can decrease the fuel consumption of vehicles by up to 3.3% at high vehicle speeds. To verify the highest numerical drag reduction, the model vehicle and vortex generators were produced in a 3-D printer. The vortex generators were mounted on the vehicle models with the lowest CD value as in CFD analysis. The wind tunnel tests were conducted under the same test conditions for two vehicle models. It was determined that the experimental results supported numerical drag reduction.


Main Subjects

Altaf, A., A. Omar and W. Asrar (2022). Passive drag reduction of the square back truck body. International Journal of Automotive and Mechanical Engineering 19-3, 9892- 9908.##
Anantha, R. L. and H. H. Rahul (2016). Methods for reducing aerodynamic drag in vehicles and thus acquiring fuel economy. Journal of Advanced Engineering Research 3(1), 26-32.##
ANSYS Fluent Tutorial Guide.pdf (
Bayindirli, C., Y. E. Akansu and M. Celik (2020). Experimental and numerical studies on improvement of drag force of a bus model using different spoiler models. International Journal Heavy Vehicle Systems 27-6, 743-776.##
Bayindirli, C. and M. Çelik (2018, 30 October-3 November). The investigation of flow structure around of a minibus model by CFD method. In IV International Academic Research Congress, 30 October-3 November, Alanya. Turkey.##
Çağan, M. (2000). Taşıt Aerodinamik Özelliklerinin Sayısal Yöntemlerle Incelenmesi, M. Sc. thesis, Istanbul Technical University, Institute of Science and Technology: Istanbul.##
Çengel, Y. A. and J. M. Cimbala (2008). Fundamentals of fluid mechanics and applications. Güven Bilimsel 562-599.##
Chen, D., H. Chen and X. Cui (2022). Dual-coupling drag reduction inspired by tuna skin: Fan-shaped imbricated fish scale composited with flexible coating. AIP Advances 12, 035218.##
Chilbule, C., A. Upadhyay and Y. Mukkamala (2014). Profile modification of truck-trailer to prune the aerodynamic drag and its repercussion on fuel consumption. Procedia Engineering 97, 1208-1219.##
Edwige, S., P. Gilotte and I. Mortazavi (2022). Computational analysis of actuation techniques impact on the flow control around the ahmed body. Fluids 7, 52.##
Ince, İ. T. (2010). Aerodynamic Analysis of GTD Model Administrative Service Vehicle. Ph. D. thesis, Gazi University Institute of Science, Ankara.##
Kajiwara, S. (2017). Passive variable rear-wing aerodynamics of an open wheel racing car. Automot. Automotive Engine Technology 2(1-4), 107-117.##
Kalaycı, C. (2021). Numerical Investigation and Optimization of Aerodynamic Performance Of An Suv Model Motor Vehicle. M. Sc. thesis, Institute Of Graduate Studıes Of Batman University.##
Kaya, F. and İ. Karagöz (2007). Investigation into the suitability of turbulence models in swirling flows. Uludağ Üniversitesi Mühendislik Fakültesi Dergisi 12 (1) 85-96.##
Kesat, T. M. (2019). Çekici Römorke Etki Eden Aerodinamik Kuvvetler Üzerine Doğadan Esinlenerek Geliştirilen Pasif Akış Kontrol Parçalarının Etkilerinin İncelenmesi. M. Sc. thesis, Karadeniz Teknik Üniversitesi Fen Bilimleri Enstitüsü.##
Nigal Ashik, P. A., P. Suseendhar, N. Manoj and S. Wasim Feroze (2020). Reduction of drag in box-type and half streamlined automobile vehicles. Materials Today: Proceedings.##
Palanivendhan, M., J. Chandradass, C. Saravanan, J. Philip and R. Sharan (2021). Reduction in aerodynamic drag acting on a commercial vehicle by using a dimpled surface. Materials Today: Proceedings 45, 7072-7078.##
Rejniak, A. A. and A. Gatto (2021). On the drag reduction of road vehicles with trailing edge-integrated lobed mixers, Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, DOI: 10.1177/09544070211039697##
Sudin, M. N., M. A. Abdullah, S. A. Shamsuddin, F. R. Ramli and M. M. Tahir (2014). Review of research on aerodynamic drag reduction methods. International Journal of Mechanical and Mechatronics Engineering IJMME-IJENS 14-2, 35-45.##
Wenshi Cui, W., H. Zhu, C. Xia and Z. Yang (2015). Comparison of steady blowing and synthetic jets for aerodynamic drag reduction of a simplified vehicle. Procedia Engineering 126, 388-392.##
Wood, R. M. and S. X. S. Bauer (2003). Simple and low-cost aerodynamic drag reduction devices for tractor-trailer trucks. SAE Technical Paper 01(3377), 1-18.##
Yadav, R., A. Islam and R. Chaturvedi (2021). Efficient reduction of the consumption of fuel in road vehicles using aerodynamic behavior in CDF analysis. Materials Today: Proceedings 45, 2773-2776##
Yanqing, W., W. Ding, W. Yuju, M. Yuan, C. Lei and W. Jiadao (2023). Aerodynamic drag reduction on speed skating helmet by surface structures. Applied Sciences 13, 130.##
Yarin, T. G. (2019). Farklı Taşıt Modellerinin Aerodinamik Yapısının Nümerik Olarak İncelenmesi. M. Sc. thesis, Bursa Uludağ Üniversitesi Fen Bilimleri Enstitüsü.##
Zhang, L., M. Yang and X. Liang (2018). Experimental study on the effect of wind angles on pressure distribution of train streamlined zone and train aerodynamic forces, Journal of Wind Engineering and Industrial Aerodynamics 174, 330-343.##
Volume 16, Issue 7
July 2023
Pages 1414-1426
  • Received: 14 January 2023
  • Revised: 21 February 2023
  • Accepted: 01 March 2023
  • Available online: 04 May 2023