ME2302 Dynamics of Machinery, B.E Question Bank : dmice.ac.in

Name of the College : DMI College OF Engineering
Department : Mechanical Engineering
Subject Name : ME 2302 Dynamics of Machinery
Degree : B.E
Sem : V
Website : dmice.ac.in
Document Type : Question Bank

Design Of Machine Elements : https://www.pdfquestion.in/uploads/dmice.ac.in/1512-ME2302.doc

DMI Dynamics of Machinery Question Bank

UNIT – I

FORCE ANALYSIS :
PART-A (2 Marks) :
1. Define static force analysis.
2.Differentiate between static and dynamic equilibrium.
3. What are the requirements of an equivalent dynamical system?.

Related : DMI College OF Engineering ME2304 Engineering Metrology And Measurement, B.E Question Bank : www.pdfquestion.in/1494.html

4. Define inertia force.
5.Define inertia torque.
6. State D’Alembert’s principle.
7.Define piston effort.
8. Define crank effort and crank-pin effort.
9.What is meant by turning moment diagram or crank effort diagram?
10.Explain the term maximum fluctuation of energy in fly wheel.

11.Define coefficient of fluctuation of energy.
12.Define coefficient of fluctuation of speed.
13.Define coefficient of steadiness.
14.Why flywheels are needed in forging and pressing operations?
15.When the correction couple should be applied?
16.Draw the turning moment diagram for four stroke IC engine.
17.Define compound pendulum or torsional pendulum.
18.Differentiate the function of flywheel and governor.
19.List out the few machines in which flywheel is used.
20.State the principle of super position.

UNIT-II

BALANCING :
PART-A (2 Marks) :
1. What is meant by balancing of rotating masses?
2. Why rotating masses are to be dynamically balanced?
3. Define static balancing.
4. Define dynamic balancing.
5. State the conditions for static and dynamic balancing.
6. State the conditions for complete balance of several masses revolving in different planes of a shaft.
7. Why complete balancing is not possible in reciprocating engine?
8. Can a single cylinder engine be fully balanced? Why?
9. Differentiate between the unbalanced force caused due to rotating and reciprocating masses.
10. Why are the cranks of a locomotive, with two cylinders, placed at 90° to each other?
11. List the effects of partial balancing of locomotives.
12. Define swaying couple.
13. Define hammer blow with respect to locomotives.
14. What are the effects of hammer blow ?
15. Define direct and reverse cranks.
16. What for the balancing machines are used?
17. What are different types of balancing machines?
18. What are the effects of swaying couple?
19.Define centrifugal force.
20.Define tractive force.

PART-B (16 Marks) :
1) Four masses m1, m2, m3 and m4 are 200 kg, 300 kg, 240 kg and 260 kg respectively. The corresponding radii of rotation are 0.2 m, 0.15 m, 0.25 m and 0.3 m respectively and the angles between successive masses are 45°, 75° and 135°. Find the position and magnitude of the balance mass required by analytical method and graphical method, if its radius of rotation is 0.2 m.

2) A shaft carries four masses in parallel planes A, B, C and D in this order along its length. The masses at B and C are 18 kg and 12.5 kg respectively, and each has an eccentricity of 60 mm. The masses at A and D have an eccentricity of 80 mm. The angle between the masses at B and C is 100° and that between the masses at B and A is 190°, both being measured in the same direction. The axial distance between the planes A and B is 100 mm and that between B and C is 200 mm. If the shaft is in complete dynamic balance, determine:
(i) The magnitude of the masses at A and D,
(ii) the distance between planes A and D and
(iii) the angular position of the mass at D.

3. The planes containing masses B and C are 300 mm apart. The angle between planes containing B and C is 90°. B and C make angles of 210° and 120° respectively with D in the same sense. Find
(i) The magnitude and the angular position of mass A
(ii) The position of planes A and D.

4) A, B, C and D are four masses carried by a rotating shaft at radii 100, 125, 200 and 150 mm respectively. The planes in which the masses revolve are spaced 600 mm apart and the mass of B, C and D are 10 kg, 5 kg, and 4 kg respectively. Find the required mass A and the relative angular settings of the four masses so that the shaft shall be in complete balance.

5) A shaft carries four masses in parallel planes A, B, C and D in this order along its length. The masses at B and C are 18 kg and 12.5 kg respectively, and each has an eccentricity of 60 mm. The masses at A and D have an eccentricity of 80 mm. The angle between the masses at B and C is 100° and that between the masses at B and A is 190°, both being measured in the same direction. The axial distance between the planes A and B is 100 mm and that between B and C is 200 mm. If the shaft is in complete dynamic balance, determine:
(i) The magnitude of the masses at A and D,
(ii) the distance between planes A and D and
(iii) the angular position of the mass at D.

6) A two-cylinder uncoupled locomotive has inside cylinders 0.6m apart . The radius of each crank is 300 mm and are at right angles . the revolving mass per cylinder = is 250 kg and the reciprocating mass per cylinder is 300 kg. The whole of the revolving and two-third of the reciprocating masses to be balanced and the balancing masses are to be placed in the planes of rotation of the driving wheels a radius of 0.8 m . the driving wheels are 2 m in diameter and 1.5 m apart. If the speed of the engine is 80 km/hr, determine
a) Hammer blow,
b) Maximum variation in tractive force
c) Maximum swaying couple.

7) The following data refer to a two cylinder locomotive:
Rotating mass per cylinder = 300 kg; reciprocating mass per cylinder = 330 kg; Distance between wheels = 1500 mm; Distance between cylinder centre = 600 mm; diameter of trends of driving wheels =1800 mm; crank radius = 325mm; radius of centre of balance mass =650 mm; Locomotive speed =60 km/hr; Angle between cylinder cranks = 90°; Dead load on each wheel = 40 kN.
Determine:
(i) The balancing mass required in the planes of driving wheels if whole of the revolving and two-third of the reciprocating mass to be balanced
(ii) The swaying couple
(iii) The variation in the tractive force
(iv) The maximum and minimum pressure on the rails and
(v) The maximum speed of locomotive without lifting the wheels from the rails