Numerical Predictions of Tip Shape Effect on Helicopter Rotor Noise in Forward Flight

Helikopter İleri Uçuşunda Farklı Pala Uç Şekillerinin Rotor Gürültüsüne Etkisinin Sayısal Tahmini

Authors

  • Tuğrul Teoman Öztürk Istanbul Technical University, Faculty of Aeronautics and Astronautics
  • Alim Rüstem Aslan Istanbul Technical University, Faculty of Aeronautics and Astronautics

Keywords:

Rotor, Helicopter, CFD, URANS, HART II, Blade Tip

Abstract

The effect of helicopter rotor blade tip shape on overall aircraft noise level is analyzed, in forward flight conditions. The infamous HART-II experimental data is used as a base for validations. Commercially available CFD software Ansys/Fluent is used to model the flow field over rotor-body interaction with moving-deforming meshes. The blades are modelled individually to match the actual physical blade geometry and blade movement. The acoustics calculations are performed via FW-H modelling of the software. HART-II blade has a rectangular blade tip planform. Four different tip shapes are modeled and analyzed in addition to the original blade planform. Baseline case of HART-II experiment is used for the predictive calculations. The predictions show that the least sound pressure level obtained by %10 c notched tip shape having 10-degree anhedral angle with 2,23 dB(A) difference amongst other four tip shapes.

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Published

31-07-2024

How to Cite

[1]
T. T. Öztürk and A. R. Aslan, “Numerical Predictions of Tip Shape Effect on Helicopter Rotor Noise in Forward Flight: Helikopter İleri Uçuşunda Farklı Pala Uç Şekillerinin Rotor Gürültüsüne Etkisinin Sayısal Tahmini”, JAST, vol. 17, no. 2, pp. 62–88, Jul. 2024.

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