PART – A (2 MARKS)
UNIT – I:
1. Define resistance.
2. What are the components of resistance?
3. Name any three resistance prediction methods?
4. What is Reynolds number? Give its formula.
5. Define thrust deduction factor.
6. Draw a typical propulsion arrangement and name the various powers involved in it.
7. Draw a typical diagram of a screw propeller and indicate the important nomenclatures.
8. What is circulation theory?
UNIT – II:
1. Define cavitation.
2. What are the different types of cavitation?
3. What is cavitation number?
4. Write short notes about open water tests.
5. What is the effect of cavitation?
6. Define sheet cavitation with neat sketch.
7. Give short notes about BP- ẟ chart.
8. List the various types of propellers.
UNIT – III:
1. Define Quasi propulsive co-efficient.
2. What are the various forces acting on the propeller blades?
3. Define lift.
4. What is drag?
5. Give short notes on propeller design charts.
6. What are the various materials used in the propeller construction?
7. Write short notes about propeller strength.
UNIT – IV:
1. Define using formula and sketch wherever required: Indicated power
1
2. Define using formula and sketch wherever required: Break power
3. Define using formula and sketch wherever required: Shaft power
4. What is the difference between the nominal wake and the effective wake?
5. What are the steps that can be taken to minimize propeller excited vibration in a ship?
6. What are the reasons for adopting unconventional propulsion devices in some ships?
7. Name the various types of propeller available?
8. Differentiate FPP and CPP.
UNIT – V:
1. List the various types of propulsion systems.
2. Give short notes on vertical axis propeller.
3. Define ITTC. What are the various functions of ITTC?
4. Write short notes about Standardization trials.
5. Why is the propeller efficiency derived from the axial momentum theory called an "ideal
efficiency"? In which condition will this efficiency be 100 percent?
6. Define Blade area ratio and expanded blade area ratio?
7. Why is the relative rotative efficiency not equal to 1 in general?
8. Define slip, real slip, apparent slip.
PART – B (16 MARKS)
UNIT – I:
1. Explain in detail axial momentum theory. Derive the formula for ideal efficiency.
2. Derive the formula for ideal efficiency circulation theory.
3. Explain blade element theory. Derive the formula for ideal efficiency.
4. Discuss about the historical development of a propeller.
5. Draw a various view of a screw propeller and explain its nomenclature.
6. Draw a typical layout of a propulsion system and explain about the various powers, efficiencies
involved in it.
UNIT – II:
2
1. Explain how cavitation affects the performance of propeller. Describe the types of cavitation.
2. What is the purpose of open water test? Its types. Briefly explain with the help proper diagram?
3. What is cavitation and explain its types.
4. Explain about the various cavitation tests.
5. How the resistance is calculated in model tests? Explain in detail about that how the model test
results are extrapolated to the actual scenario.
6. Explain about the various types of resistance.
UNIT – III:
1. Explain with diagram, which are the parameters considered for propeller design?
2. Discuss in detail about Effect of propeller diameter, RPM, Number of blades, radial distribution
of loading, blade outline, Camber and angle of attack and skew angle.
3. What are the assumptions made to find out the strength of propeller blade?
4. The open water characteristics of the propeller of 0.8 pitch ratio are as follows:
J 0 0.2000 0.4000 0.6000 0.8000
KT 0.3400 0.2870 0.2182 0.1336 0.0332
10KQ 0.4000 0.3568 0.2905 0.2010 0.0883
If these results are obtained by running a model propeller of 0.2m diameter at 3000rpm over a
range of speeds in fresh water, determine (a) the power of the motor required to drive the
propeller (neglecting losses) (b) the maximum thrust, (c) the maximum open water efficiency (d)
the speed at which maximum efficiency occurs (e) the speed at which the propeller has zero thrust
and (f) the effective pitch factor, i.e the ratio of the effective pitch to the face pitch of the
propeller.
5. A ship has a speed of 18.0 knots when its engine has a brake power of 10000 KW at 150rpm. The
engine is directly connected to the propeller which has a diameter of 6.0 m. The effective power
of ship is 6700 Kw and the propeller produces a thrust of 900 KN. The open water characteristics
of the propeller are given by:
KT = 0.319 – 0.527 J + 0.169 J2
10KQ = 0.354 – 0.578 J + 0.203 J2.
Determine the propulsive efficiency and their component based on the thrust identity. The
shafting efficiency is 0.970.
3
UNIT – IV:
1. A ship of length 100 m and wetted surface of 2700 m 2 has a speed of 15 knots. A 4.0 m long
geometrically similarly model of the ship has a total resistance of 25.0 N at the corresponding
speed. Determine the total resistance of the ship assuming a forma factor of 1.05.
2. Write a short note on the following: 1) Controllable Pitch Propeller 2) Fixed Pitch Propeller.
3. Explain in detail about the Water Jet Propulsion and Super Cavitating propellers.
4. With a help of neat sketch explain about azimuth propeller.
5. Write down the steps involved in the propeller design if P, D and V are known
UNIT – V:
1. Explain about the various types of materials used for a propeller construction.
2. What are the methodical charts used in propeller design? Explain the same.
3. Define hull efficiency. Derive ŋH = (1-t) / (1-w).
4. State the similarities to be observed in conducting the open water test of a propeller. Which are
the similarities being possible to achieve in practice? Why?
5. What is the effect of propeller behind the hull? Explain with the neat sketch, what are the various
clearances to be made in between hull, propeller and rudder.
