Effects of Temperature on Magnetorheological Fluid Elastomeric Lag Dampers for Helicopter Rotors

摘要: A snubber type magnetorheological fluid elastomeric (MRFE) lag damper was developed as a retrofit to fluid-elastomeric (FE) provide adaptive lead-lag damping augmentation for hingeless helicopter rotor. This MRFE consists of flexible cylindrical body, center wall fitted with two MR flow valves, through which enclosed in the body can pass and be activated by magnetic field valve. During normal operation, is exposed temperature variations due ambient temperatures in-service self-heating. To characterize performance at different operating temperatures, tested fixed frame under rotor in-plane bending frequency (lag/rev) varying from 20°C 50°C. Complex modulus equivalent viscous were used compare characteristics baseline passive FE damper. The field-off comparable all test temperatures. significant controllable range also observed current applied valves conditions. account non-linear hysteresis behavior damper, hydromechanical model formulated based on lumped parameters. In study, accounts Model Parameters established each valve geometry, material property measured data. then accurately simulate force time history lag/rev frequency.