Aerodynamic Improvements of Buses Inspired by Beluga Whales

Document Type : Regular Article


Department of Mechanical Engineering, Manisa Celal Bayar University, Muradiye, Yunusemre, Turkey



The innovative bus designs, inspired by the whales, have been developed. The designs are confined to the frontal area of the buses. The new designs are named as the Beluga buses. Several variants of the models all mimicking Beluga whales are proposed. Both numerical analysis and experimental have been conducted to determine the drag coefficients of various models. The ANSYS CFD program was used for numerical simulations. WT tests were conducted to experimentally determine the drag coefficients. Both methods indicate that the beluga-inspired buses offer significant reductions in drag, which can lead to lower fuel consumption. The new beluga design is expected to reduce fuel consumption by 12.64%. Comparing the experimental and numerical results, a 6.4% discrepancy in the drag coefficients is observed at low Reynolds numbers, which became negligible at higher Reynolds numbers. The new geometry is expected to offer an economical solution for reducing fuel consumption.


Main Subjects

Ahmad, N. E., Aboserie, E., & Gaylard, A. (2010). Mesh optimization for ground vehicle Aerodynamics, CFD Letters, 2(1), 54–65.
Alamaan, A., Ashraf, A. O., & Waqar, A. (2014). Passive drag reduction of square back road vehicles. Journal of Wind Engineering and Industrial Aerodynamics, 134, 30-43.
Belzile, M., Patten, J., McAuliffe, B., Mayda, W., & Tanguay, B. (2012). Technical report: review of aerodynamic drag reduction devices for heavy trucks and buses. Project, 54-A3578
Benyus, J. M. (2002). Biomimicry: Innovation inspired by nature perennial. New York.
Bhave, A., & Taherian, H. (2014). Aerodynamics of intercity bus and its impact on co2 reductions. Proceedings of the 14th Annual Early Career Technical Conf.  The University of Alabama Birmingham, USA, 165-172.
Daimler, A. G., & Mercedes-Benz (2011). Consept vehicles and visions Evolution of Innovations 96-97. )
Ferziger, J. H., Peric, M., & Street R. L. (2019). Computational methods for fluid dynamics. Springer Verlag.
Fish, F. E., Weber, P. W., Murray, M. M., & Howle, L. E. (2011). The tubercles on humpback whales’ flippers: Application of bio-inspired technology. Integrative and Comparative Biology, 51(1), 203–213.
Fluent, ANSYS, (2012). Ansys Fluent 14.5 User’s Guide. ANSYS, Inc., Canonsburg, PA.
Fred, B. (2005). Reducing Aerodynamic Drag and Fuel Consumption Global Climate and Energy Project    Workshop on Advanced Transportation Stanford University, ABD 5.
Håkansson, C.  &Lenngren, M. J. (2010). CFD analysis of aerodynamic trailer devices for drag reduction of heavy duty trucks. Master’s Thesis, Automotive Engineering Chalmers University of Technology Göteborg Sweden . (Access date: 16.04.2015)
Hu, X., & Wong, T. (2011). A numerical study on rear-spoiler of passenger vehicle. World Academy of Science Engineering and Technology, 81 636–641.
Jasak, H. (1996). Error analysis and estimation for finite volume method with applications to fluid flow [PhD thesis, Department of Mechanical Engineering]. Imperial College of Science, Technology and Medicine, London.
Jones, W. P., & Launder, B. E. (1973). The prediction of laminarization with a two-equation model of turbulence, international journal of heat and mass transfer. Physics Engineering, 14, 119-132.
Launder, B. E., & Spalding, D. B. (1974). The numerical computation of turbulent flows. Computer Methods in Applied Mechanics and Engineering 3(2), 269–289.
Mohamed, E. A., Radhwi, M. N., & Abdel Gawad, A. F. (2015). Computational investigation of aerodynamic characteristics and drag reduction of a bus model American Journal of Aerospace Engineering, 2(1), 64-73.
Nowak, R. M. (1991). Walker's mammals of the world 2. (5 ed.) Baltimore: The Johns Hopkins University    Press ISBN 0-8018-5789-9.
Patil, C. N., Shashishekar, K. S., Balasubramanian, A. K., & Subbaramaiah, S. V. (2012). Aerodynamic study and drag coefficient optimization of passenger vehicle. International Journal of Engineering Research & Technology, 1(7).
Roy, S., & Srinivasan, P. (2000). External flow analysis of a truck for drag reduction International Truck and Bus Meeting & Exposition, 01(2000)3500.
Singha, S., Zunaid, M., Ansari, N. A., Bahirani, S., Dhall, S., & Kumar, S. (2014). Numerical study of the generic sports utility vehicle design with a drag reduction Add-On device. Journal of Computational Engineering, ID:785294, 1-17.
Sudin, M. Z., Abdullah, M. A., Shamsuddin, S. A., Ramli, F. R., & Tahir, M. M., (2014) Review of research on vehicles drag reduction methods. Int Journal of Mechanical & Mechatronics Engineering, 14(2), 35-47.
Trinh, M. H., Do, T. Q., & Nguyen, T. H. (2022). Study on the dynamic instability of a bus in crosswind conditions. Engineering and Technology for Sustainable Development, 32(1) 43-51.
Wilcox, D. C. (1988). Reassessment of the scale-determining equation for advanced turbulence models, AIAA Journal 26 (11), 1299– 1310.
Wilcox, D. C. (2006). Turbulence modeling for CFD. DC W Industries.
Wilcox, D. C. (2008). Formulation of the k-ɷ turbulence model revisited, AIAA Journal 46 (11), 2823–2838.
Wood, R. (2015). Reynolds number impact on commercial vehicle aerodynamics and performance, SAE International Journal of Commercial Vehicles, 8(2), 590-667.
Yan, Y. Y. (2007). Recent advances in computational simulation of macro, meso and micro-scale biomimetics related fluid flow problems. Journal of Bionic Engineering, 4(2), 97–107.
Yudianto, A., Sofyan, H., & Fauzi, N. A. (2022). Aerodynamic characteristics of overtaking bus under crosswind: CFD investigation. CFD Letters, 14(8), 20-32.