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Q9. During normal engine operation, a turbocharger rapidly loses speed and the speed reduction is accompanied by appreciable noise -

A. State with reasons the possible causes.

B. Explain in detail how the engine might be safely operated if the damage caused by this incident is such that the turbocharger cannot function.

C. State with reasons the factors which may limit engine operating speed with the turbocharger out of operation.

Q2. (a) Why exhaust outlet of marine diesel engine turbocharger is lower than inlet temperature? (6)

(b) Why do we need an air cooler and why is the scavenge air temperature maintained at 40°C? (10)

Q4. Referring to latest developments in Turbo charger application in marine diesel engines, write short notes on the following:-

(a) Power turbines Generators.

(b) Hybrid Turbo Chargers.

(c) Electro-assist Turbo chargers.

Q9. With reference to Main Engine Turbo charger

(a) What are the indication of water leakage in turbo charger casing. (8)

(b) Precaution to be taken during water washing at sea (8)

Q4. Many modern turbochargers use sleeve type bearings for rotor support.

A. Explain the reasons for their preference over the rolling contact bearings;

B. With a sketch describe the lubricating system provided for this type;

C. In a turbocharger with integral type of bearings, describe the procedure for renewing the bearings.

Q8. Sketch and describe a turbocharger-bearing lubrication system. State the type of bearing employed and explain the advantages and disadvantages of the lubricating system described.

Q1. With reference to main engine turbochargers. (4X4)

a) Give a reason why binding wire is frequently fitted near the top of the blades.

b) Mention one fault that occasionally develops with binding wire in service.

c) Define the cause and identification under running conditions of turbine blade damage.

d) State how (c) can be largely avoided.

Q3. Describe, with the aid of sketches, a system of turbo-charging a two-stroke cycle main engine. State the routine attention, which should be given to the turbo-charger. Which parameters are to be recorded during watch keeping? (16)