BE Mechanical 2003 Structure - K. K. Wagh Education Society

Balancing of rotating masses in one and several planes, balancing of.
reciprocating masses in single and multicylinder engines-inclined, radial and vee
type.Primary and secondary balancing analysis. Concept of, direct and reverse
cranks. Static and dynamic balancing machines.
5. Vibrations:
Introduction, S.H.M., degrees of freedom.
(a) Single degree of freedom system:
(i) Undamped free vibrations, damped free vibrations, over damped,
critically damped and underdamped vibrations, logarithmic decrement,
viscous .damping and dry friction/Coloumbs damping.
(ii) Forced vibrations: constant harmonic excitation, excitation due to
reciprocating and rotating unbalance, vibration isolation and
transmissibility and applications
(iii) Torsional vibrations: Single degree of freedom system of free,
undamped, damped and forced torsional vibrations. Study of two rotor
systems, geared rotor system and three-rotor system.
(b) Critical speed: Whirling of horizontal and vertical shafts carrying single rotor,
damped and undamped systems.
(c) Vibration measurements: Measurement of displacement, velocity,
acceleration, frequency and damping. Different types of pick-ups, exciters,
vibration meter and related instrumentation .
Term Work :
The term work shall consist of any 'eight' of the following experiments:
1. To determine the 'characteristic curve of a centrifugal governor and to find its
coefficient of insensitiveness and stability.