All of the following statements are correct, except,
Mass does not depend on altitude, so natural frequency remains unaffected.
The critical speed of the shaft depends upon
Critical speed of a shaft is nothing but its natural frequency and it is
K = stiffness of the shaft.
m = mass of the shaft
The equation: represents
Since excitation force is absent in the equation hence it is the equation of free, damped vibration.
The governing equation of a specific simple vibrating system is
The system is subjected to
Since excitation force is present in the equation hence it is the equation of forced vibration.
The static deflection of a shaft under a flywheel is 4 mm. Take g = 10 m/s2. What is the critical speed in rad/s?
Critical speed in rad/s2
A flexible rotor-shaft system comprises of a 10 kg rotor disc placed in the middle of a massless shaft of diameter 30 mm and length 500 mm between bearings (shaft is being taken massless as the equivalent mass of the shaft is included in the rotor mass) mounted at the ends. The shaft is made of steel for which the value of E is 2.1 x 1011 Pa. What is the critical speed of rotation of the shaft.
For shaft loaded at middle with mass M
Moment of inertia
So deflection of shaft
When a body is subjected ,to transverse vibration, the stress induced in the body will be
In case of transverse vibration, bending stresses are generated
Whirling speed of a shaft coincides with the natural frequency of its
Whirling of shaft occurs when the natural frequency of transverse vibration matches with the frequency of rotating shaft.
For given figure shows a spring mass system where the mass m is fixed in between two springs of stiffness s1 and s2. What is the equivalent spring stiffness
Since the springs are connected in parallel
seq = s1 + s2
The rate of decay of oscillations is known as
Natural logarithm of the amplitude reduction factor is known as logarithmic decrement.