PREVIOUS YEAR QUESTIONS OF S.G.P.

STEAM GENERATION & POWER

ME 311 E

PREVIOUS YEAR QUESTIONS OF S.G.P.

1.     Give the construction and working of the Babcock and Wilcox boiler?

2.    What do you understand by Boiler mountings and accessories? List different mountings and accessories generally used in a boiler?

3.  Explain working of Lancashire boiler by a neat diagrammatic sketch showing the path of hot flue gases?

4. Define and differentiate between mountings and accessories? Give three examples of each?

5. Define the Boiler mountings and accessories: explain the working of one mounting and one accessory?

6.   With the help of neat sketch explain the working of Lancashire boiler?

7. Discuss how the steam generators are classified. Give examples of each classification?

8.    With the help of neat sketch, explain the working of locomotive steam boiler. How is it different from a boiler used for locomotives? 

9.     What are steam Boiler? Explain Locomotive Boiler with diagram?

10.  Differentiate between Water tube Boiler and fire tube boiler?

11.  Different between fire tube and water tube boiler?

12.  Discuss working of fusible plug and feed check valve?

13.  What is the function of a fusible plug and where is it located in a boiler?

14. What is Boiler draught? Differentiate between natural and artificial  draught?

15.  What do you understand by the term ‘Boiler draught’? List different types of draught used in usual practice?

16.  Define the term Boiler efficiency and Equivalent evaporation?

17.  A turbine rotor disc is 0.6 m diameter at the blade ring. And is keyed to a 50 mm diameter shaft. if the minimum thickness is 9.5 mm, what should be the thickness at the shaft for a uniform stress of 200N mm² at 10,000 rpm ? Density = 7700 kg/m³?

18.  Calculate the height of chimney required to produce a draught equivalent to 1.7 cm of water if the flue gas temperature is 270⁰c and ambient temperature is 22⁰ c and minimum amount of air per kg of fuel is 17 kg?

19.  What do understand by chimney draught? How is it classified?

20.  Explain binary vapors cycle?

21.  Describe the ranking cycle using superheated steam show in what respect cycle differs from the Carnot cycle between the same temperature limit?

22.  What are super saturation and its effects in nozzle?

23.  If a ring of mean radius R is acted upon by equal and opposite pulls P along a diameter, find expressions for the maximum bending moment and the deflection along the line of P?

24.  List different limitations of Carnot cycle when steam is used as working medium?

25.  State the methods of increasing the thermal efficiency of a ranking cycle?

26.  A turbine is supplied with steam at a pressure of 32 bar & 410⁰ c. the steam then expands to a pressure of 0.08 bar isentropic ally. Find the dryness fraction at the end of expansion & thermal efficiency of the cycle considers pump work?

27.  Explain the working of a binary vapor cycle?

28.  What are the advantages of compound steam engine over single stage steam engine?

29.  The steam is supplied at a pressure of 8.4 bar and cut off accurse at 0.35 of the stroke .the back pressure is 1.25 bar .if the diagram factor is 0.75, determine the actual mean effective pressure. Neglect clearance?

30.  In a regenerative cycle the inlet conditions are 40 bar & 400⁰ c. Steam is bled at 10 bar in regenerative heating using close feed water heater.  The exit pressure is 0.8 bars. Neglecting pump work, determine efficiency of the cycle?

31.  List the advantages of reheating?

32.  Discuss the methods of governing a simple steam engine?

33.  A 5 cm. by 3 cm .by 0.5 cm angle is used as a cantilever of length 50 cm.with the 3 cm. horizontal. A load of 1000N is applied at the free end. Determine the position of neutral axis and maximum stress set up?

34.  Explain Carnot cycle with diagram?

35.  Compare Carnot cycle and ranking cycle?

36.  Derive an expression for the mass flow rate of steam thigh a nozzle?

37.  Dry saturated steam enters a nozzle at a pressure of 10 bar and with an initial velocity of 90 m/s. the outlet pressure is 6 bar and the outlet velocity is 435 m/s. the heat loss from the nozzle is 9 kHz/kg of steam flow .calculate the dryness fraction and the area at the exit, if the Area inlet is 1256 mm?

38.  Estimate the mass flow rate of steam in a nozzle with the following data: inlet pressure and temperature = 13 bar and 2500c; back pressure = 1.0 bar: throat diameter = 12 mm?

39.  What is the physical significance of critical pressure of a nozzle?

40.  Define critical pressure ratio for the nozzle of the steam turbine .obtain analytically its value in terms of the index of expansion. State the assumptions made?

41.  Explain Mach Numbers sketch the shape of nozzle?

42.  Dry saturated steam at a pressure of 11 bars enters a convergent – divergent nozzle and leaves at a pressure of 2 bar. If the flow is adiabatic & frictionless: determine (I) the exit velocity of steam and (ii) ratio of area at exit and at throat .take n = 1.135?

43.  Prove that maximum flow rate per unit area through a nozzle occurs   when the ratio of pressure at throat to inlet pressure is equal to {2/(n+1)}n/(n-1) where n= isentropic index of expansion?

44.  Explain supersaturated floe in steam nozzle and degree of super saturation and degree of under cooling?

45. A closed coiled helical spring is to have a stiffness of 900 N/m compression with a maximum load of 45 n and maximum shearing stress of 120 N/mm2. The solid’ length of the spring is 45 mm. find the wire diameter, mean coil radius and number of coils. G=40,000 N/mm2?

46.  Draw the inlet and the outlet velocity triangles for an impulse turbine. And derive an expression for power produced by the turbine and axial thrust on the wheel?

47.  In a de level turbine, the steam enters wheel through a nozzle with a velocity of 500m/s and at an angle of 200 to the direction of motion of the blade. The blade speed is 200 m/s and the exit angle of the moving blade is 250. Find the inlet angle of the moving blade, exit velocity of steam and its direction and work done per kg of steam?

48.  Derive an expression for the mass flow rate of steam discharged through a nozzle?

49.  With the help of mathematical equation discuss the shape of nozzle for different value of match number at inlet of the nozzle?

50.  Steam having pressure of 10.5 bars and 0.95 dry is expanded through a convergent –divergent nozzle and pressure of steam leaving the nozzle is 0.85 bars. Find the velocity at the throat for maximum discharge?

51.  Explain the phenomenon of super saturated flow through the nozzle?

52.  Define the term vacuum efficiency. Why is vacuum maintained the condenser of a steam power plant?

53.  Discuss the merits and demerits of surface condenser and jet condenser. Which type is recommended for large plants?

54.  A straight length of steel bar, 1.5 m. long and 2 cm. × 0.5 cm. section is compressed longitudinally until it buckles. Assuming Euler’s formula to apply to this case ,estimate the maximum central deflection before the steel passes the yield point of 320 MPA take E = 210 GPA?

55.  Define balding efficiency .stage efficiency and nozzle efficiency?

56.  Draw and explain Rankin cycle?

57.  Derive the expression for maximum blade efficiency in a single stage steam turbine?

58.  What do you mean by compounding of steam turbine? Also explain velocity compounded steam turbine?

59.  What do you mean by compounding of steam turbine? Discuss pressure velocity compounded steam turbine?

60.  What do you understand by ‘governing of steam turbine’? Describe any one method?

61.  A steel tube has a mean diameter of 120 mm. and a thickness of 2 mm. calculate the torque which can be transmitted by the tube with a factor of safety 3 if the criterion of failure is (a) maximum stress (b) maximum shear  strain energy and (c) maximum shear strain energy. The elastic limit of steel in tension is 225 MN/m2 and poisons ratio v is 0.3?

62.  In an impulse steam the mean diameter of the blades is 1.05 m and speed is 3000 rpm. The nozzle angle is 200, the ratio of blade sped of steam speed is 0.42 and the ratio of relative velocity at outlet from the blades to that at inlet is 0.84. The outlet angle of blade is to be made 30 less then inlet. The mass of steam flowing through the turbine per second is 10.0 kg. Calculate: (i) blade angle (ii) relative velocity of steam entering the blades (iii) power developed & blade efficiency (iv)Tangential force on the blades?

63.  Draw and explain tandem type compound engine?

64.  A compound steam engine is to develop 260 KW when taking steam is 150 m/min. the cut off in the H.P cylinder is to be 0.4 and the cylinder volume is 3.7.allow a diagram factor of 0.83 for the combined cards and determine suitable dimensions’ of cylinders. If the diagrams factor for the H.P. cylinder alone is 0.85, determine the separate powers developed in the two cylinders when the L.P cut off is arranged to give equal initial loads on piston. Assume hyperbolic and neglect clearance effects?

65.  Define the condenser efficiency: vacuum efficiency used is a steam condenser?

66.  What do you understand by governing of steam turbine? Explain throttle governing?

67.  Discuss the features of parson’s turbine. What is its working principle?

68.  A reaction turbine running at 360 rpm consumes 5 kg of steam per second. The leakage is 10%. The discharge blade tip angle for both moving and fixed blades is 200. The axial velocity of flow is 0.75 times the blade velocity .the power developed by a certain pair is 4.8 KW. Where the pressure is 2 bar and dryness fraction is 0.95. Find the drum diameter and blades height?

69.  A certain stage of a parson’s turbine consists of one row of fixed blades & one row of moving blades. The details of the turbine are as below:

The mean diameter of the blades = 68 cm

RPM of the turbine = 3000

The mass of steam passing per second = 13.5 kg

Steam velocity at exit from fixed blades = 143.7 m/s

The blade outlet angle = 200

Calculate (i) the power developed in the stage (ii) gross stage efficiency?

70.  Write short notes on a.) Asymmetric bending b.) Leaf Springs?

71.  Writes short notes for the following a.)Natural & Artificial draft b.)Governing of steam turbines c.)Compare forced draught and induced draught?

72.  Attempt any two of the following a.)Binary vapors power cycle b.)Air –extraction pumps?

73.  The vacuum at the extraction pipe in a condenser is 710 mm of mercury and the temperature is 35.820C .The barometer reads 760 mm of mercury .the air leakage into the condenser is 4 kg per 10,000 kg of steam .determine a.)The volume of air to be dealt with by the dry air pump per kg of steam entering the condenser b.)The mass of water vapors associated with this air take R = 287 J/KG-K for air?

74.  Write short notes on the following a.)Delton’s law of partial pressure b.)Vacuum efficiency?

75.  Explain following with diagram:

·        Water Lever indicator

·        Dead Weight Safety Valve

·        Spring Loaded safety valve

·        Blow off Cock.