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    Unit 5

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    Rohit Ghulanavar
    This document contains a question bank with 19 questions related to applied thermodynamics and steam turbines. The questions cover topics such as compounding, h-s diagrams, impulse and reaction turbines, velocity diagrams, efficiency calculations, axial thrust calculations, and reheat factors. Specifically, questions ask about calculating power developed, diagram efficiency, axial thrust, and proving expressions for maximum blade efficiency.

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    © All Rights Reserved
    Download as DOCX, PDF, TXT or read online from Scribd

    Unit 5

    Uploaded by

    Rohit Ghulanavar
    154 views3 pages
    This document contains a question bank with 19 questions related to applied thermodynamics and steam turbines. The questions cover topics such as compounding, h-s diagrams, impulse and reaction turbines, velocity diagrams, efficiency calculations, axial thrust calculations, and reheat factors. Specifically, questions ask about calculating power developed, diagram efficiency, axial thrust, and proving expressions for maximum blade efficiency.

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    ATD Unit 5 Assignment

    Original Title

    UNIT 5

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    This document contains a question bank with 19 questions related to applied thermodynamics and steam turbines. The questions cover topics such as compounding, h-s diagrams, impulse and reaction turbines, velocity diagrams, efficiency calculations, axial thrust calculations, and reheat factors. Specifically, questions ask about calculating power developed, diagram efficiency, axial thrust, and proving expressions for maximum blade efficiency.

    Copyright:

    © All Rights Reserved
    Download as DOCX, PDF, TXT or read online from Scribd
    Download as docx, pdf, or txt
    154 views3 pages

    Unit 5

    Uploaded by

    Rohit Ghulanavar
    This document contains a question bank with 19 questions related to applied thermodynamics and steam turbines. The questions cover topics such as compounding, h-s diagrams, impulse and reaction turbines, velocity diagrams, efficiency calculations, axial thrust calculations, and reheat factors. Specifically, questions ask about calculating power developed, diagram efficiency, axial thrust, and proving expressions for maximum blade efficiency.

    Copyright:

    © All Rights Reserved
    Download as DOCX, PDF, TXT or read online from Scribd
    Download as docx, pdf, or txt
    of 3

    SANT GAJANAN MAHARAJ COLLEGE OF ENGINEERING, MAHAGAON

    DEPARTMENT OF MECHANICAL ENGINEERING

    Subject : Applied Thermodynamics (ATD)

    UNIT NO. – 05 (QUESTION BANK)

    1. What is compounding? Explain any one method with sketch in detail.


    2. With the help of h-s diagram explain reheat factor.
    3. The velocity of steam exiting the nozzle of impulse stage of turbine is 400 m/s. The blades operate close to the
    maximum blading efficiency. The nozzle angle is 20 0. Considering equitriangular blades and neglecting blade
    friction calculate for steam flow of 0.6 kg/s, the diagram power and diagram efficiency.
    4. What is fundamental difference between the operation of impulse & reaction turbine. Explain the same with
    sketch.
    5. Steam with absolute velocity of 300 m/s is supplied through a nozzle to a single stage impulse turbine. The
    nozzle angle is 25o. The mean diameter of blade rotor is 100cm & it has a speed of 2000 r.p.m. find suitable
    blade angles for zero axial thrust. If blade velocity coefficient is 0.9 & the steam flow rate is 10 kg/s, calculate
    the power developed.
    6. Explain the term reheat factor. Why its magnitude is always greater than unity.
    7. Draw a combined velocity triangle for a single stage impulse turbine &obtain expression for work done per
    stage, blade efficiency & axial thrust.
    8. The main diameter of the blades of an impulse turbine with a single, wheel is 105cm & the speed is 3000rpm.
    The nozzle angle is 180, the ratio of blade is 0.42 & the ratio of the relative velocity outlet from the blade to that
    at inlet is 0.84. The steam flow rate is 8kg/sec. draw velocity diagram for the blades & calculate.
    I) Tangential thrust
    II) Power developed by blade
    III) Blade efficiency

    9. Define the following


    I) Speed ratio
    II) Blade velocity coefficient
    III) Diagram efficiency
    IV) Stage efficiency
    10. The blade speed of a single ring impulse is 250m/s & nozzle angle is 20 0. The heat drop in nozzle is 550 kJ/kg &
    nozzle efficiency is 0.85. The blade discharge angle is 30 0& machine develops 30 kW when consuming 360 kg
    of steam per hour. Draw velocity diagram & calculate:
    i) axial thrust on blading
    ii) heat equivalent per kg of steam due to friction of blading
    2 cos 2 α
    11. Prove that maximum blade efficiency of a 50% single stage reaction turbine is given by ηb= when α
    1+ cos 2 α
    is nozzle angle or outlet angle of fixed blade.
    12. The following data relate to a single stage impulse turbine.
    Steam velocity=600m/s
    Blade speed =250m/s
    Nozzle angle=200
    Blade outlet angle=250
    Neglect the effect of friction, & calculate the work developed by the turbine for the steam flow rate of 20 kg/s.
    also calculates the axial thrust on the bearings.

    13. A velocity compounded impulse turbine has two rows of moving blades with a fixed row of guide blades. The
    steam leaves the nozzle at 900m/s in a direction at 18 0 to the plane of rotation. The blade speed is 150m/s &
    blade outlet angles are 240, 260, &300 for the first moving, first fixed & second moving respectively. The friction
    factor is 0.9 for all rows. The steam supply is 4500 kg/hr.
    14. Following is the data pertaining to a single row impulse turbines:
    Mean diameter of blade4 ring=2m; speed 3000 rpm; nozzle angle=18 0;ratio of blade velocity to steam
    velocity=0.5; blade friction factor =0.9; blade angle at exit =30 more than at inlet; steam supply=30,000kg/h.
    Draw velocity diagram for the moving blade & estimate
    i) power developed
    ii) diagram efficiency &
    iii) steam consumption kg/kwh.
    16) Show that blade efficiency of single stage impulse turbine
    ηb=2(1+KB)(ρcosα1-ρ2) & further prove that ηb(max)=cos2α1.
    17) In a De-Laval turbine steam issues from the nozzle with a velocity of 1200m/sec. the nozzle angle is 20 0, the
    mean blade velocity is 400m/sec & the inlet & outlet angles of blades are equal. The mass of steam flowing
    through the turbine per hour is 1000kg.
    Calculate
    i) Blade angles
    ii) Relative velocity of steam entering the blades
    iii) Tangential force on the blades &
    iv) Power developed.
    18) State the advantages & disadvantages of reheating if steam.
    19) Explain “bleeding of steam turbines”.

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