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Seat No.: Enrolment
GUJARAT TECHNOLOGICAL UNIVERSITY
ME- SEMESTER-I • EXAMINATION -SUMMER 2018
Subject Code: 2713305 Date: 10/05/2018
Subject Name: Hydropower Engineering
Time: 02:30 PM to 05:00 PM Total Marks: 70
Instructions:
1. Attempt all questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
Q.1

Draw plan of Hydropower plant and Explain function of each component.
07

Differentiate between hydropower plant and thermal power plant with reference to Indian condition.
07
Q.2

What are the main parts of the Pelton turbine. Explain each part of Pelton turbine with sketch.
07

Calculate annual load factor, plant use factor and capacity factor for a power station having following details. Station works for 2500 hours during the year
Total units generated per year 60 x 106 kwh
Capacity of station 30MW
Maximum demand 22MW
07
OR

A penstock with an internal diameter of 1.2m supplies water at a head equivalent to 17.6 kg/cm2. There is a possibility of 20 percent increase in the pressure due to transient conditions. The design stress and the efficiency of the joint may be assumed to be 1020 kg/cm2 and 85 percent respectively. Calculate the approximate wall thickness of the penstock required.
07
Q.3

Define the following terms
Load curve
Firm Power
Draft Tube
Capacity factor
Power factor
07

What is meant by economical diameter of a penstock? How can it be found out?
07
OR
Q.3

What do you understand by water hammer in pipe line? Derive the expressions for the water hammer pressure in case of a rigid pipe and in case of an elastic pipe.
07

What are the functions of a surge tank? Describe with neat sketches the behavior of various types of surge tanks.
07
Q.4

If daily flow in a river is 20 m3/s. What would be the firm capacity of run of river plant to be used as an 8 hour peaking station? What would be the pondage factor and the magnitude of the pondage? Head of the plant 15m and overall Efficiency 80%.
07

Explain the following terms Trash rack Pondage factor Air Vent
07
OR
Q.4

Give classification of turbines and Explain Francis turbines with a neat sketch.
07

Explain the different type of Intake Structures.
07
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Q.5

What is draft tube? Explain different types of draft tubes in brief with sketches. Derive an equation of efficiency of draft tube.
07

Write design criteria of Penstock
07
OR
Q.5

Write a short notes on Cavitation in turbines
07

A hydroelectric station is to be supplied with 10 m3/sec of water through a penstock which has a friction factor of 0.016. The maximum head on the penstock is 50 kg/cm2 and a water hammer overpressure of 20% over the normal pressure is anticipated. The safe stress in the steel used is presumed to be 3000 kg/cm2. The ready penstocks at site are likely to cost Rs. 15000 per tonne including erection charges. The life of the project is 50 years and the rate of interest is 7%. It is proposed to sell the energy at the rate of Rs. 0.03/kWh. What should be the optimum diameter of the penstock, given that the OMR costs are Assume the turbine efficiency to be 85% and the annual load factor as 0.4
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