Current Science

Open Access Open Access  Restricted Access Subscription Access

Reducing Wing Observability to Radar using Microserrations at the Leading Edge


Affiliations
1 Department of Aerospace Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
 

Serrations are found in nature on the leading edge (LE) of bird wings and whale flippers. These serrations reduce flight noise and improve aerodynamic performance. This has inspired LE serrations to be incorporated in the design of aircraft wings and turbine blades. LE of wings can contribute significantly to observability of aircraft by radar due to LE diffraction of horizontally polarized incident electromagnetic (EM) waves. Serrations at the wing LE can also be used to reduce observability to radar under such circumstances. In the present study, the method of equivalent currents is used to analyse the effect of microserrations on an infinitesimally thin metallic delta wing. It is shown that microserrations at the wing LE can be effectively used to control backscatter due to diffraction of EM waves at the wing LE. LE serrations, in general, work by introducing a randomness in the interaction of wing LE with incident fluid flow or EM field.

Keywords

Computational Electromagnetics, Leading Edge, Radar Cross-Section, Serrations, Wing Observability.
User
Notifications
Font Size

  • Lilley, G. M., A study of the silent flight of the owl. In 4th AIAA/CEAS Aeroacoustics Conference, Toulouse, France, AIAA Paper 1998–2340, 1998.

  • Fish, F. E., Weber, P. W., Murray, M. M. and Howle, L. E., The tubercles on humpback whales’ flippers: application of bioinspired technology. Integr. Comp. Biol., 2011, 51, 203–213.

  • Choi, H., Park, H., Sagong, W. and Lee, S.-I., Biomimetic flow control based on morphological features of living creatures. Phys. Fluids, 2012, 24, 121302-1–121302-20.

  • Hersh, A. S., Soderman, P. T. and Hayden, R. E., Investigation of acoustic effects of leading-edge serrations on airfoils. J. Aircraft, 1974, 11, 197–202.

  • Knott, E. F., Shaeffer, J. and Tuley, M., Radar Cross Section. Institution of Engineering and Technology, Electromagnetics and Radar Series, SciTech Publishing, 2004, 2nd edn, pp. 200–267.

  • Teja, T. S., Vaghela, M. B. and Chatterjee, A., Reducing aircraft radar cross-section with owl wing type serrated trailing edge. Curr. Sci., 2017, 112, 1020–1023.

  • Lu, L.-J., Chen, H.-Y., Zhou, P.-H., Liang, D.-F. and Deng, L.-J., Design of controlling edge scattering based on tapered periodic surfaces loading. In Proceedings of Progress in Electromagnetics Research Symposium, Guangzhou, China, 2014.

  • Rao, S. M., Time Domain Electromagnetics, Academic Press, San Diego, 1999, pp. 307–365.

  • Michaeli, A., Equivalent edge currents for arbitrary aspects of observation. IEEE Trans. Antennas Propag., 1984, 32, 252–258.

  • Panayappan, K. and Mittra, R., A technique for handling multiscale electromagnetic problems using the finite difference time domain (FDTD) algorithm. J. Electromag. Waves Appl., 2016, 30, 1241–1264.

  • Balanis, C. A., Advanced Engineering Electromagnetics, John Wiley, New York, 1989, pp. 285–291.

  • Van Ewijk, L. J., Diffraction computation by means of the method of equivalent currents. TNO Physics and Electronics Laboratory report, The Hague, Netherlands, FEL-94-B195, 1994.


Abstract Views: 227

PDF Views: 75




  • Reducing Wing Observability to Radar using Microserrations at the Leading Edge

Abstract Views: 227  |  PDF Views: 75

Authors

Karri Sai Krishna Reddy
Department of Aerospace Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
Avijit Chatterjee
Department of Aerospace Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India

Abstract


Serrations are found in nature on the leading edge (LE) of bird wings and whale flippers. These serrations reduce flight noise and improve aerodynamic performance. This has inspired LE serrations to be incorporated in the design of aircraft wings and turbine blades. LE of wings can contribute significantly to observability of aircraft by radar due to LE diffraction of horizontally polarized incident electromagnetic (EM) waves. Serrations at the wing LE can also be used to reduce observability to radar under such circumstances. In the present study, the method of equivalent currents is used to analyse the effect of microserrations on an infinitesimally thin metallic delta wing. It is shown that microserrations at the wing LE can be effectively used to control backscatter due to diffraction of EM waves at the wing LE. LE serrations, in general, work by introducing a randomness in the interaction of wing LE with incident fluid flow or EM field.

Keywords


Computational Electromagnetics, Leading Edge, Radar Cross-Section, Serrations, Wing Observability.

References





DOI: https://doi.org/10.18520/cs%2Fv116%2Fi10%2F1731-1734