REDUCING TURBO-GENERATOR NOISE AND VIBRATIONS WITH DYNAMIC ABSORBERS

摘要

The presence of a pronounced hum, at a FRANCE frequency of 100 Hz, in the turbine hall is attributed to the turbogenerator sets. This constitutes a high rate of noise pollution and vibrations at 108 Hz may be the cause of material damage. As conventional soundproofing methods have proven to be inadequate in the reduction of emitted sound at 180 Hz, studies have been orientated towards the development of dynamic absorbers as a means of reducing vibration of the machines and therefore their emitted noise level. Use of such absorbers requires knowledge of the vibrational behaviour of turbogenerators as well as of the occurrence of resonance at 100 Hz. To assess the suitability of dynamic absorbers the following analyses have been made: vibrational analysis of the set running normally, modal analysis of the turbogenerator around 100 Hz, computed simulation of structural modifications to the turbogenerator due to the addition of dynamic absorbers tuned for a frequency of 100 Hz, dynamic calculation of a stator by finished elements, construction of a model and comparison with results of experiments, final design of a dynamic absorber, installation, adjustment and checking of efficiency of dynamic absorber.