Abstract
The improvement of the fuel efficiency of heavy vehicles has received considerable attention. Thus, various flow-control devices have been implemented to reduce aerodynamic drag exerting on heavy vehicles. In this study, we proposed noble boat tail with lower inclined air deflector (LIAD), as a passive flow-control device on attached at the rear end of heavy vehicles. The aerodynamic performance of the modified boat tail with LIAD is experimentally examined by measuring the drag force, side force exerting on a real-shaped heavy vehicle model at various yawing angles. As a result, the maximum drag reduction effect of the boat tail with LIAD (θ = 45°) is about 9.02% compared to the result without the boat tail, although the length of the bottom tail is half of that of four-way boat tail. Furthermore, particle image velocimetry velocity field measurements were conducted to investigate the modified flow structure are by the attachment of various boat tails. Consequently, the LIAD effectively suppresses the formation of large-scale recirculating zone in the wake behind the rear body of the vehicle, as an effective guide of the underbody flow.
Graphical Abstract
Similar content being viewed by others
References
Ahmed S, Ramm G, Faitin G (1984) Some salient features of the time-averaged ground vehicle wake. Society of Automotive Engineers Inc, Warrendale
Ahmed S, Gawthorpe R, Mackrodt P-A (1985) Aerodynamics of road-and rail vehicles. Vehicle Syst Dyn 14:319–392
Allan J (1981) Aerodynamic drag and pressure measurements on a simplified tractor-trailer model. J Wind Eng Ind Aerodyn 9:125–136
Beaudoin J-F, Aider J-L (2008) Drag and lift reduction of a 3D bluff body using flaps. Exp Fluids 44:491–501
Beaudoin J, Cadot O, Aider J, Gosse K, Paranthoën P, Hamelin B, Tissier M, Allano D, Mutabazi I, Gonzales M (2004) Cavitation as a complementary tool for automotive aerodynamics. Exp Fluids 37:763–768
Bradley R (2000) Technology roadmap for the 21st century truck program. Energy efficiency and renewable energy. US Department of Energy, Washington, DC, p 32
Choi H, Lee J, Park H (2014) Aerodynamics of heavy vehicles. Annu Rev Fluid Mech 46:441–468
Cooper KR (2003) Truck aerodynamics reborn: lessons from the past. SAE Trans 112:132–142
Fourrié G, Keirsbulck L, Labraga L, Gilliéron P (2011) Bluff-body drag reduction using a deflector. Exp Fluids 50:385–395
Gad-el-Hak M (2000) Flow control: passive, active and reactive flow management. Cambridge University Press, Cambridge
Han T, Sumantran V, Harris C, Kuzmanov T, Huebler M, Zak T (1996) Flow-field simulations of three simplified vehicle shapes and comparisons with experimental measurements. SAE Technical Paper, No. 960678
Hucho W-H, Sovran G (1993) Aerodynamics of road vehicles. Annu Rev Fluid Mech 25:485–537
Khalighi B, Zhang S, Koromilas C, Balkanyi S, Bernal LP, Iaccarino G, Moin P (2001) Experimental and computational study of unsteady wake flow behind a bluff body with a drag reduction device. SAE paper, No. 1042
Leuschen J, Cooper KR (2006) Full-scale wind tunnel tests of production and prototype, second-generation aerodynamic drag-reducing devices for tractor-trailers. SAE Technical Paper, No. 3456
Malviya V, Mishra R, Fieldhouse J (2009) CFD investigation of a novel fuel-saving device for articulated tractor-trailer combinations. Eng Appl Comput Fluid Mech 3:587–607
McCallen R, Couch R, Hsu J, Browand F, Hammache M, Leonard A, Brady M, Salari K, Rutledge W, Ross J (1999) Progress in reducing aerodynamic drag for higher efficiency of heavy duty trucks (class 7–8). Society of Automotive Engineers, Incorporated
McCallen R, Browand F, Ross J (2013) The aerodynamics of heavy vehicles: trucks, buses, and trains. Springer Science & Business Media, Berlin
Minguez M, Pasquetti R, Serre E (2008) High-order large-eddy simulation of flow over the “Ahmed body” car model. Phys Fluids 20:095101
Ortega J, Salari K, Brown A, Schoon R (2013) Aerodynamic drag reduction of class 8 heavy vehicles: a full-scale wind tunnel study. Lawrence Livermore National Laboratory technical report, LLNL-TR-628153
Roumeas M, Gilliéron P, Kourta A (2009) Analysis and control of the near-wake flow over a square-back geometry. Comput Fluids 38:60–70
SAE (2012) SAE wind tunnel test procedure for trucks and buses. SAE Recommended Practice J 1252
Verzicco R, Fatica M, Iaccarino G, Moin P, Khalighi B (2002) Large eddy simulation of a road vehicle with drag-reduction devices. AIAA J 40:2447–2455
West G, Apelt C (1982) The effects of tunnel blockage and aspect ratio on the mean flow past a circular cylinder with Reynolds numbers between 104 and 105. J Fluid Mech 114:361–377
Acknowledgements
This study was supported by the KAIA in the Ministry of Land, Infrastructure, and Transport through the research project entitled Development of aerodynamic technologies for efficient road freight transport.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Lee, E.J., Lee, S.J. Drag reduction of a heavy vehicle using a modified boat tail with lower inclined air deflector. J Vis 20, 743–752 (2017). https://doi.org/10.1007/s12650-017-0426-6
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12650-017-0426-6