International Scientific Journal


Iosif Taposu has formulated a mathematical model and generated a family of airfoils whose geometry resembles the dolphin shape. These airfoils are characterized by a sharp leading edge and experiments have proven that they can achieve better aerodynamic characteristics at very high angles of attack than certain classical airfoils, with the nose geometry inclined downwards. On the other hand, they have not been applied to any commercial general aviation aircraft. The authors of this paper have been motivated to compare the aerodynamic characteristics of widely used NACA 2415 airfoil with Taposu’s Dolphin that would have the same principal geometric characteristics. A CFD calculation model has been established and applied on NACA 2415. The results were compared with NACA experiments and very good agreements have been achieved in the major domains of lift and polar curves. The same CFD model has been applied on the counterpart Dolphin 2415. Results have shown that the Dolphin has a slightly higher lift/drag ratio in the lift coefficient domain 0.1-0.35 than NACA. On the other hand, at higher and lower lift coefficients, its aerodynamic characteristics were drastically below those of the NACA section, due to the unfavorable influence of the Dolphin’s sharp nose. A series of the Dolphin’s leading edge modifications has been investigated, gradually improving its aerodynamics. Finally, version M4, consisting of about 70% of Dolphin’s original rear domain and 30% of the new nose shape, managed to exceed the NACA’s characteristics, thus paving the way to investigate the Dolphin hybrids that could be suitable for the general aviation industry.
PAPER REVISED: 2021-05-28
PAPER ACCEPTED: 2021-06-01
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2022, VOLUME 26, ISSUE Issue 3, PAGES [2199 - 2210]
  1. Vincent, J. F., et al., Biomimetics: its practice and theory, Journal of the Royal Society, Interface, 3, (2006), 9, pp. 471-482
  2. Gibbs- Smith., Ch., Sir George Cayley's Aeronautics 1796- 1855, Science Museum Her Majesty's stationery office, London, 1962
  3. Huang, W., et al., Research on aerodynamic performance of a novel dolphin head-shaped bionic airfoil, Energy, 214 (2021), Article 118179
  4. Taposu, I., Spataru, P., About the Experimental Results of a Dolphin Profile at Low Speeds, 18th Applied Aerodynamics Conference, Denver, CO, USA, 2000, pp. 762-771
  5. Taposu, I., Profilele delfin. Un nou concept în aerodinamică (The Dolphin Profiles. A new Concept in Aerodynamics, in Romanian), S.C. Editura Technica S.A., Bucharest, Romania, 2002
  6. Berbente, C., Danaila, S., On the aerodynamic characteristics of a class of airfoils with continuous curvature at subsonic, transonic and supersonic regimes, Scientific Bulletin U.P.B., 69, (2007), 1, pp. 15- 28
  7. Ivanov, T., et al, Influence of selected turbulence model on the optimization of a class-shape transformation parameterized airfoil, Thermal Science, 21, (2017), pp. 737-744
  8. Peigin, S., et al., Unmanned air vehicle 3-D wing aerodynamical design and algorithm stability with respect to initial shape, Thermal Science, 23, (2019), pp. 599-605
  9. Ocokoljic, G., et al., Aerodynamic shape optimization of guided missile based on wind tunnel testing and computational fluid dynamics simulation, Thermal Science, 21, (2017), pp. 1543-1554
  10. Abbott, I. H., et al., Summary of Airfoil Data Report NACA Report No. 824, National Advisory Committee for Aeronautics, USA, 1945
  11. ANSYS FLUENT 16.0, Theory Guide, ANSYS Inc, Canonsburg, PA, (2015)
  12. Menter, F. R., Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications, AIAA Journal, 32, (1994), 8, pp. 1598-1605
  13. Turbulence Modeling Resource, NASA Langley Research Center,
  14. Menter, F.R., Improved two-equation k-omega turbulence models for aerodynamic flows, NASA STI/Recon Technical Report, 1992
  15. Kostić, O., Numerička simulacija strujnog polja vazduha u nadzvučnom mlazniku sa preprekom na izlazu (Computational Simulation of Air Flow in Supersonic Nozzle with Obstacle at Exit, in Serbian), Doctoral Disertation, University of Belgrade, Faculty of Mechanical Engineering, Belgrade, 2016
  16. Kostić, O., et al, CFD Modeling of Supersonic Airflow Generated by 2D Nozzle With and Without an Obstacle at the Exit Section, FME Transactions, 42, (2015), 2, pp. 107-113
  17. Kostić, O., et al, Comparative CFD Analyses of a 2D Supersonic Nozzle Flow with Jet Tab and Jet Vane, Tehnički vjesnik - Technical Gazette, 24, (2017), 5. , pp. 1335-1344

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence