HYBRID FRICTION-IMPACT VIBRATION DAMPER FOR CRYOGENIC ROTATING MACHINERY

A hybrid friction-impact rotordynamic damper has been designed and tes ted in a high-speed rotordynamic test rig for application to rocket en gine turbopumps operating at cryogenic temperatures, such as the high- pressure oxygen and fuel turbopumps used in the Space Shuttle Main Eng ines. Test results have shown the impact damper to be effective at lar ger amplitudes and higher frequencies, whereas the friction damper is effective at lower amplitudes and frequencies. Together, the hybrid da mper offers good performance over a wide range of operating conditions . A friction damper design methodology is presented and applied to the experimental test rig.