The static tests results for all investigated composite blade models show that the blade with the Rohacell 71 Polyurethane foam core, designated as model 1, performed best with regard to the torsional and flexional characteristics. In all three cases, the elastic axis position was practically the same, i.e. at 25% of the crosssection's airfoil cord. The results from the blade frequency analysis show an exceptional conformity of the basic modes as well as their oscillation frequencies for all three types of blades. The obtained differences in frequencies and displacement vectors for some basic types of oscillation modes were within the range 1 -6-5-6%. The structural damping tests indicate that the blade with the Rohacell 71 Polyurethane foam core has the least structural damping and two times less than the blades with Nomex aramid honeycomb core. Well designed composite laminated structures can provide a satisfactory level of damping and a high degree of damage tolerance; however, in practice, it is still very difficult to utilise the full fibre strength potential of composite structures. The composite laminated materials with adequate core give constructions with exceptional high level structural damping so important in the aircraft application.
Experimental study of structural damping of composite helicopter blades with different cores
Experimentelle Untersuchung der strukturellen Dämpfung von Hubschrauberrotoren aus Verbundwerkstoffen mit unterschiedlichen Kernschichten
Plastics, Rubber and Composites ; 39 , 1 ; 1-5
2010
5 Seiten, 14 Bilder, 1 Tabelle, 8 Quellen
Aufsatz (Zeitschrift)
Englisch
experimentelle Untersuchung , Schwingungsdämpfung , Hubschrauber , Rotor (Drehflügel) , Schichtverbundwerkstoff , Zwischenschicht , Polyurethanschaumstoff , Aramid , Wabenstruktur , Phenolharz , Produktvergleich , Verdrehungswiderstand , Biegesteifigkeit , statisches Messverfahren , Sandwich-Bauweise , Außenhaut , Glasgewebe
Engineering Index Backfile | 1959
|Thermal Deicing of Polymer Composite Helicopter Blades
British Library Conference Proceedings | 2005
|Online Contents | 1994
Thermal deicing of polymer composite helicopter blades
Tema Archiv | 2005
|Engineering Index Backfile | 1955