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what is the advantages and dis advantages of critical
speed of turbine
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Answer Posted / ashok ghadge
Turbine shaft is having its natural own frequency and due
to passing of steam shaft got forced frequency, when these
frequencies match (At critical speed) the sinusidal waves
of vibrations match and vibration amplitude is equal to
addition of respective amplitude of two waves. This gives
large amplitude for vibrations to the shaft. In such
situation shaft may fail.
Adv. Such critical speeds should be imediately overtaken to
safeguard the shaft.
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