Subject 2014 Question Paper — Government College of Engineering and T…

Instructions

• Attempt any Five questions in all, selecting at least two questions from each section.
• Assume missing data if required.

Questions

SECTION - A

• Q1. a) The average monthly inflow (cumecs) of a river are (45, 20, 30, 70, 40, 10, 100, 120, 80, 65, 55, 50) in the months of January to December in a year. Draw the flow duration curve and power duration curve. Determine. (10) i) Firm power ii) Power at 90% iii) 50% dependability iv) storage required at 50% water availability b) State briefly storage and pondage. What is the essential difference between the two, illustrate with a sketch. (10) [20 marks]
• Q2. a) Give brief account of salient features of low head plants with regard to head, topography, Discharge, storage and generation cost. (10) b) Discuss the followings (10) i) Utilization factor ii) Plant factor iii) Load factor iv) secondary power [20 marks]
• Q3. a) A runoff stream station with an installed capacity of 25000 KV operates at $30\%$ load factor when it serves as a peak load station. What should be minimum discharge in the stream so that the station may serve as the peak load station? The plant efficiency may be taken as $80\%$ when working under a head of $20\text{ m}$. Also calculate the maximum load factor of the plant when the discharge in the stream rises to 35 cumecs. (10) b) Explain how do you assess the water power potential of a hydroelectric scheme. (10) [20 marks]
• Q4. Give a brief account of (20) a) Necessity for the development of pumped storage power in the country. b) Mention the advantages and limitations of the development of pump storage plants. [20 marks]

SECTION - B

• Q5. a) A dam $6\text{ m}$ high and $1.5\text{ m}$ wide at the top has vertical water face. Find the base width of the dam if no tension is to develop. Take unit weight of masonary as $20\text{ kN/m}^3$ and $c=1$. Investigate the stability of the dam if the coefficient of friction is 0.6 and maximum allowable compressive stress is $1600\text{ kN/m}^2$. (10) b) What is most economical central angle for a constant radius arch dam and obtain expression for the same. (10) [20 marks]
• Q6. a) At an energy dissipater structure below a low spillway. The discharge is 19 cumecs and the energy loss is $1\text{ m}$ at hydraulic jump forming therein. Calculate the depths of flow at both ends of the jumps. (10) b) Explain the various layouts of a power house. (10) [20 marks]
• Q7. a) Determine the economical diameter of penstock pipe $500\text{ m}$ long to carry water to a turbine having output of $1000\text{ kW}$ at $90\%$ efficiency against head of $150\text{ m}$. Assume $f=0.023$. (10) b) What do you understand by surge tank? Illustrate with sketches its different types. (10) [20 marks]
• Q8. Write short notes on the followings : (20) a) Foreway b) Cavitation in turbines c) Specific speed of turbine d) Features of a Kaplan turbine. [20 marks]