Theoretical and experimental investigation of a ground resonance phenomenon for the ILX-27 UAV helicopter

• Autorzy: Kowaleczko G. , Gorecki T.

Identyfikatory

DOI

10.5604/01.3001.0010.3155

• Języki publikacji: EN

Abstrakty

EN

Ground resonance is an unbalance of the helicopter main rotor rotation caused by its asymmetry. Whilst the helicopter is in contact with the ground this asymmetry generates a divergent and often destructive oscillations of the helicopter structure. These oscillations are self-excited. This paper present results of both theoretical and experimental investigations of this phenomenon. They were dedicated to the new polish UAV helicopter ILX-27. The theoretical analysis were done with commercial software ANSYS using Finite Element Method. The virtual model of the helicopter model accurately reproduced the geometry of all elements of the helicopter and was easy to modify to simulate various kinds of damages. Calculations were done for the following cases: C1 – the helicopter standing on the ground with zero thrust of the rotor, C2 = C1 + helicopter with additional support of the rotor mast, C3 = C2 + thrust of the rotor equal to the total mass of the helicopter, C4 = C2 + fixing the helicopter to the ground, C5 = C2 + helicopter with additional mass. At the beginning the modal analysis for all cases was done – natural frequencies and modes of the structure were identified. Next, for selected cases, harmonic analysis was performed – the structure of the helicopter was loaded with concentrated harmonic forces. Finally the dynamic analysis gave time courses of blades and the hub center motions in the case of structural damages. All phases of simulations were correlated with ground tests of the helicopter prototype. This allowed to compare results of theoretical investigations. These results also supported tests of the prototype.

Słowa kluczowe

EN

ground resonance; dynamics of helicopter structure; finite element method; simulation; ground tests

• Wydawca: Łukasiewicz Research Network - Institute of Aviation ; European Science Society of Powertrain and Transport KONES Poland ; Wydawnictwo Instytutu Technicznego Wojsk Lotniczych
• Czasopismo: Journal of KONES
• Rocznik: 2017
• Tom: Vol. 24, No. 4
• Strony: 91--98
• Opis fizyczny: Bibliogr. 17 poz., rys.

Twórcy

autor

Kowaleczko G.

• Air Force Institute of Technology Księcia Bolesława Street 6, 01-494 Warsaw, Poland tel.: [phone], fax: [phone]

autor

Gorecki T.

• Air Force Institute of Technology Księcia Bolesława Street 6, 01-494 Warsaw, Poland tel.: [phone], fax: [phone]

Bibliografia

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Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).