S p e c if ic a t io n s
Date : 2017. 3. 27.
Title
Procurement of Elastomeric Lead-lag Dampers of Small
Scale Rotor Hub for Rotor Wind Tunnel Test
Model
Elastomeric lead-lag damper
Specificati
on
(1) Configuration
- Damper length between two rod end bearings is 85mm.
- The diameter or width of damper is less than 35mm.
(2) Damper loads
- Damper should withstand the maximum tension load of 600N and the
maximum compression load of 900N.
(3) Stiffness and damping
- Elastomeric dampers have the characteristics of elastic and damping and
complex stiffness is expressed as follows
K* = K' + j×K"
- Target stiffness and damping values of a damper
- Primary operating frequency for damper design is 1/rev and damper should
be designed to match the target values of stiffness and damping at 1/rev
requirements within 20% tolerance.
(4) Test
- Acceptance test reports for dampers should be provided.
Frequency
K′ (N/mm)
K″(N/mm)
14.4 Hz(0.5/rev)
239
67
28.7 Hz(1/rev)
327
100