JNTUA B.Tech. R20 Regulations

########## JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY ANANTAPUR B.Tech (ME) - III-II Sem L T P C 3 0 0 3 (20A03601) DYNAMICS OF MACHINERY

####### Course Objectives:

- • Analysis of forces acting in mechanisms
- • Effects of unbalance forces
- • Modelling and analyzing the vibration behaviour of spring mass damper system
- • The principles in mechanisms used for governing of machines

######## Course the end of the course, the student will be able to Course the end of the course, the student will be able to Outcomes: A

- • Determine the forces acting on various linkages when a mechanism is subjected to external forces.
- • Identify and correct the unbalances of rotating body
- • Analyze the vibratory motion of SDOF systems.
- • Reduce the magnitude of vibration and isolate vibration of dynamic systems
- • Determine dimensions of Governors for speed control.

########## UNIT I Friction and Power Screws

Friction: Inclined plane, friction of screws and nuts, pivot and collar, uniform pressure, uniform wear. Friction circle and friction axis, lubricated surfaces, boundary friction, film lubrication. Power screws: Forms of threads, self locking of screws, efficiency of different screws, Square, trapezoidal, screw threads.

########## UNIT II Precession, Turning Moment Diagram and Fly Wheel

Precession: Gyroscopes, effect of precession motion on the stability of moving vehicles such as motor car, motorcycle, aeroplanes and ships. Turning Moment Diagrams and Fly Wheels: Turning moment diagrams for steam engine, IC Engine and multi cylinder engine. Crank effort - coefficient of Fluctuation of energy, coefficient of Fluctuation of speed - Fly wheels and their design, Fly wheels for Punching machines.

########## UNIT III Governors

Watt, Porter and Proell governors. Spring loaded governors - Hartnell and Hartung governors with auxiliary springs. Sensitiveness, isochronism and hunting. Effort and power of a governor. UNIT IV Balancing Balancing: Balancing of rotating masses - single and multiple - single and different planes. Balancing Of Reciprocating Masses: Primary and Secondary balancing of reciprocating masses. Analytical and graphical methods. Unbalanced forces and couples - V-engine, multi cylinder inline and radial engines for primary and secondary balancing.

########## UNIT V Vibration

Free and forced vibration of single degree of freedom system, Role of damping, whirling of shafts and critical speeds. Simple problems on free, forced and damped vibrations. Vibration Isolation & Transmissibility. Transverse vibrations of beams with concen trated and distributed loads. Dunkerly's method, Raleigh's method. Torsional vibrations - two and three rotor systems.

######### Textbooks:

- 1. S.S. Rattan, Theory of Machines, MGHPublishers,3/e,2013.
- 2. R.L. Norton, Kinematics and Dynamics of Machinery, Tata McGraw Hill, 2017.

######### Reference Books:

- 1. Thomas Bevan, Theory of machines, Pearson, 3/e,2012.
- 2. J.E. Shigley, The theory of machines and mechanisms, McGraw hill, 2/e, 1995.
- 3. R.S.Khurmi, J.K.Guptha, Theory of machines S. Chand publications, 2005.

######### Online Learning Resources:

- • https://nptel.ac.in/courses/112104114
- • https://nptel.ac.in/courses/112101096
- • https://archive.org/details/NPTEL-MechEngr-Dynamics\_of\_Machines
- • https://www.youtube.com/watch?v=OlZXxPVpmBs
- • https://www.digimat.in/nptel/courses/video/112104114/L01.html