Leikykh D. Identification of reasons of asynchronous vibrations excitation for turbo-compressors rotors and methods of reducing their amplitudes.

Dissertation is devoted to identification of reasons of asynchronous vibrations excitation for turbo-compressors rotors and methods of decreasing their amplitudes, and includes development of design method of discrete multiweight non-linear mathematical models of turbo-compressors rotors for researching effect of titling pad bearings, internal friction and other parameters on rotor behavior in range of stable and unstable frequencies of rotation. On the basis of developed method, specific non-linear models of rotor systems for different types of titling pad bearings have been identified. Effect of different models of internal friction on stability and nature of polyharmonic vibrations of rotors have been researched. Experimental researches of turbo-compressor rotor dynamics at different types of bearings have been conducted. Values of limiting speed of rotor depending of unbalance have been determined upon test results. Also, stability limit of model rotor at changing temperature of oil supplied to bearing for different types of bearings has been experimentally obtained, dependence of changing limit speed of rotor on diametrical clearance for segment five shoe bearing and effect of oil pressure supplied to bearing on rotor vibration state have been researched. The researched object is vibration state of turbo-compressor flexible rotor defined by effecting non-linear effects of titling pad bearings.