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F1040 Pages: 4

vibration of the system will be at the centre of the length BC
2. The natural frequency of the torsional vibrations
What is whirling speed of a shaft. Prove that the whirling speed for a rotating (5)
shaft is the same as the frequency of natural transverse vibration.
Calculate the whirling speed of a shaft 20 mm diameter and 0.6 m long carrying (5)

a mass of 1 kg at its mid-point. The density of the shaft material is 40 Mg/m?,

and Young’s modulus is 200 GN/m?. Assume the shaft to be freely supported

A single cylinder diesel engine drives a centrifugal pump. The rotating mass of (10)
the engine, flywheel and the pump with the shaft is equivalent to a three rotor
system. The mass moment of inertia of engine, flywheel and the pump are 0.15,
0.3,and 0.09kgm? respectively .The diameter of the shaft is 70mm and the centre
distance between engine rotating masses, flywheel and the pump are 1.5m and

Im. Find the natural frequencies of the torsional vibrations, Take G=84kN/mm/.

اد ‎RR‏ بد

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