LEWIS RESEARCH CENTER SPIN RIG AND ITS USE IN VIBRATION ANALYSIS OF ROTATING SYSTEMS.
The Lewis Research Center spin rig was constructed to provide experimental evaluation of analysis methods developed under the NASA Engine Structural Dynamics Program. Rotors up to 51 cm (20in. ) in diameter can be spun to 16,000 rpm up to 51 cm (20 in. ) in diameter can be spun to 16,000 rpm in vacuum by air motor. Vibration forcing functions are provided by shakers tha apply oscillatory axial forces or transverse moments to the shaft, by a natural whirling of the shaft, and by air jet. Blade vibration is detected by strain gages and optical tip blade-motion sensors. A variety of analog and digital processing equipment is used to display and analyze the signals. Results obtained from two rotors are discussed.