Design High Pressure Boilers B.E Question Paper : jaduniv.edu.in
Name of the University : Jadavpur University
Department : Power Engineering
Degree : B.E
Subject Name : Design High Pressure Boilers
Sem : II
Website : jaduniv.edu.in
Document Type : Model Question Paper
Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/dspace.jdvu.ac.in/6160-Design%20High%20Pressure%20Boilers.pdf
Jadavpur Design High Pressure Boilers Question Paper
B. Power Engg. Final Examination, 2007 :
(2nd Semester)
Time : Three hours
Full Marks : 100
Related : Jadavpur University Material & Processes B.E Question Paper : www.pdfquestion.in/6159.html
Answer any five questions. :
1. a) Classify boiler based on use of steam. 2
b) In a high capacity boiler operating on reheat cycle, heat available for being absorbed is 525 MW. Explain as a designes how will you distribute this heat in different sections. 8
c) State important features of a high pressure high capacity boiler of our country. 10
2. a) What is natural circulation ? 2
b) Explain the factors that influences natural circulation.8
c) State and explain principle of natural circulation with suitable diagram. 8
c) When does natural circulation cease ? 2
3. a) Explain how superheater and reheater surfaces of a large radiant boiler is located. Why such arrangements are adopted give reasons. 12
b) What are plater elements ? Why are they so called ? What are their special design and constructional features ? 8
4. a) What are the sources of impurities of boiler-turbine condenser system operating on closed cycle ? 5
b) How is desired condition of drum water maintained ? 5
c) State and explain the methods adopted for maintaining desired drum water condition. 10
5. a) What are different forms of internal and external deposits observed in boiler tubes ? 8
b) Explain mechanism of formation of each of them. 10
c) Explain how clean boiler condition can be maintained.
6. a) Explain the basic criteria of section of material for pressure parts of boiler. 5
b) What are alloying elements ? Explain how they improve quality of boiler steel. 5
c) Calculate minimum thickness and ordered thickness of a steam outlet header with following data 10
Steam temperature 540°C, Pressure 184 Kg/cm2g. Diameter 219.1 mm Material of construction chromium Molybdenum steel having following properties :
Minimum specified tensile strength at room temperature is 490 N/mm2.
Yield point stress at 500 and 550°C are 190 and 168 N/mm2.
Average stress to produce rupture in 100,000 hours at temperature of 530, 540 and 550°C are 98, 84 and 72 N/mm2 respectively.
Two rows of 20.5 OD tubes are connected to the header at axial pitch of 120 mm and circumferential pitch of 60 angle.
Corrosion allowance 0.8 mm.
Header manufacturing tolerance 10%.
7. Write few lines on : 4×5=20
a) Luminous and non luminous radiation
b) Departure from nucleate boiling
c) Volumetric heat release of a furnace
d) Neutral line of boiler expansion.
Power Engineering New Syllabus :
Steam Generator :
Classification and application of boilers, fire and water tube boiler, Utility steam generator fundamentals; types of coal firing- stoker, PF, cyclone and fluidized bed firing; Boiler furnace, furnace design, types and arrangement of coal and oil burners, flame scanners and ignitors; Boiler draft and air flow control.
Boiling heat transfer, nucleate and film boiling, DNB; Circulation principles, Features of forced circulation and critical pressure boilers, once through and super-critical pressure boilers, Boiler mountings and accessories, Steam drum & drum internals, Steam water separation; Waterwall, superheater, reheater, economizer, heat transfer and fluid flow through different elements, disposition and calculations of heating surfaces, air preheaters, boiler casing and insulations, Superheater steam temperature adjustment and control, Boiler losses, Performance and heat balance. Fluidized Bed Boilers: Types, merits and demerits.
Steam Turbine And Condenser :
Principle of action of steam turbine; clarification, relative advantages of steam turbine as prime mover, different components of steam turbine & their functions, Ideal and Actual flow of compressible fluid through nozzle, nozzle shape, critical pressure ratio, maximum rate of discharge, under expansion and over expansion in nozzle. Nozzle efficiency & velocity coefficient of nozzles. Supersaturated flow through nozzle, Flow of steam through simple impulse turbine blading, velocity diagram, blade efficiency, Gross stage efficiency, net stage efficiency, optimum velocity ratio.
Degree of admission. Multistaging or Compounding of impulse turbine, velocity compounding, pressure compounding, velocity and pressure compounding, reheat factor, Internal efficiency, state point locus etc. Flow of steam through Reaction turbine, velocity diagram, Degree of reaction, blade height, stage efficiency, optimum velocity ratio, axial thrust in reaction turbine.