- Tytuł:
- Structure fatigue crack in the effect of acoustic load : case study
- Autorzy:
- Wiśniowski, W.
- Powiązania:
- https://bibliotekanauki.pl/articles/244957.pdf
- Data publikacji:
- 2014
- Wydawca:
- Instytut Techniczny Wojsk Lotniczych
- Tematy:
-
acoustic loads
resonance tests
fatigue cracks - Opis:
- The paper presents a method for detection mechanisms and prevention of the fatigue cracks caused by acoustic loads acting on the aircraft elevator structure. During aircraft inspection, the fatigue cracks in elevator rib caps were discovered. The theory emerged, that cracks were caused by acoustic extortion on elevator sheet covering, caused by jet engine exhaust airstream, engine gas flow expanding in convergent nozzle and acting as the source of the strong acoustic load. To prove this theory, investigations were arranged, in which the strains in the elevator sheet skin, between the ribs area, were determined in harmonic excitation. The results, after frequency analysis, showed strong resonance in 270 Hz area. Mode of this resonance caused drumming of covering, resulting in bending of the ribs caps and causing them to fail from fatigue. Changes in elevator design raised the resonance frequency and lowered strains in modified elevator covering. The changes mainly increased sheet-covering stiffness by increase of thickness and lowering the sheet-metal covering mass in selected places, mainly by technological means - metal bonding (gluing) and metal covering chemical milling.
- Źródło:
-
Journal of KONES; 2014, 21, 4; 533-536
1231-4005
2354-0133 - Pojawia się w:
- Journal of KONES
- Dostawca treści:
- Biblioteka Nauki
Artykuł