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

Abstract Views: 345  |  PDF Views: 112

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