ME-603-A Turbo Machinery - May 2022 Question Paper

Under each question, How to answer lists the points an answer should cover, outlined by CampusPrep from the syllabus. Check the details against your textbook.

1. 7 Marks
   aDescribe second law of thermodynamic how it is related to boiler.
   How to answer

   • Statement of second law of thermodynamics - Kelvin-Planck and Clausius statements
   • Relevance to heat engine and boiler as heat source
   • Application to boiler efficiency and irreversibility
   • T-s diagram concept for steam generation
2. 7 Marks
   bWhat is the role of entropy in the definition of second law of thermodynamics?
   How to answer

   • Definition of entropy as measure of disorder / irreversibility
   • Clausius inequality and entropy change
   • Role in defining direction and feasibility of processes
   • Application to second law formulation
3. 7 Marks
   aWrite down the expression for equivalent evaporation for steam generator.
   How to answer

   • Definition of equivalent evaporation
   • Formula $E = m(h-h_f)/2257$ per kg fuel
   • Meaning of from and at 1006C
   • Variables: steam mass, enthalpy, feed water enthalpy
4. 7 Marks
   bDescribe any one type of boiler in detail.
   How to answer

   • Name and classification of boiler selected
   • Construction and main components with sketch
   • Working principle and steam generation process
   • Advantages, limitations and applications
5. 7 Marks
   aDraw velocity diagram of impulse steam turbine.
   How to answer

   • Inlet and outlet velocity triangles with $V, U, V_r, V_w, V_f$
   • Nozzle and moving blade angles
   • Impulse condition: symmetrical or pressure drop only in nozzle
   • Work and efficiency relation from diagram
6. 7 Marks
   bHow velocity diagram of steam turbine and hydro turbine are related to each other?
   How to answer

   • Basis of velocity triangles common to both machines
   • Working fluid difference: steam compressible vs water incompressible
   • Energy transfer - Euler turbine equation applicability
   • Similarities in inlet/outlet triangles and differences in design
7. 7 Marks
   aWhat do you mean by manometric head of any hydro turbine?
   How to answer

   • Definition of manometric head in pumps/turbines context
   • Components: static head, losses and velocity head
   • Significance for hydro machines
   • Formula expression
8. 7 Marks
   bFind out the expression for power produced for any steam turbine.
   How to answer

   • Euler work from velocity triangles $P = m U \Delta V_w$
   • Expression in terms of mass flow, blade speed and whirl components
   • Use of stage efficiency and enthalpy drop
   • Final power formula for steam turbine
9. 7 Marks
   aExplain the term degree of reaction for steam turbine.
   How to answer

   • Definition: ratio of enthalpy drop in moving blades to total stage drop
   • Formula $R = \Delta h_{moving}/\Delta h_{stage}$
   • Values for impulse (0) and 50% reaction
   • Effect on velocity diagram and efficiency
10. 7 Marks
    bExplain vector diagram of axial flow compressor.
    How to answer

    • Inlet and outlet vector triangles for rotor and stator
    • Axial velocity, blade speed and flow angles
    • Work input and pressure rise across stage
    • Degree of reaction representation
11. 7 Marks
    aWrite down the effect of blade and nozzle losses on vane efficiency.
    How to answer

    • Blade friction and nozzle loss coefficients
    • Reduction in relative and absolute velocities
    • Effect on vane/blading efficiency formula
    • T-s representation of losses
12. 7 Marks
    bWhat do you mean by stage efficiency of steam turbine?
    How to answer

    • Definition: useful work vs enthalpy drop in stage
    • Difference from blade and overall efficiency
    • Formula with reheating and losses
    • Significance in multistage turbines
13. 7 Marks
    aState the difference between hydraulic mechanical and overall efficiency of hydro turbine.
    How to answer

    • Definitions of hydraulic, mechanical and overall efficiency
    • Formulas and power flow between them
    • Tabular comparison of numerator/denominator
    • Relation $\eta_o = \eta_h \times \eta_m$
14. 7 Marks
    bWrite down the application of power transmitting devices at industry level.
    How to answer

    • Role of couplings, gears, belts, fluid drives
    • Industrial applications: pumps, compressors, conveyors
    • Power transmission in process plants
    • Examples at industry level
15. 7 Marks
    aWhat is torque convertor where it is used?
    How to answer

    • Definition and construction: pump, turbine and stator
    • Torque multiplication principle
    • Applications in automobiles and industrial drives
    • Difference from fluid coupling
16. 7 Marks
    bWhat are Positive Displacement Pump?
    How to answer

    • Definition: trapping and displacing fixed fluid volume
    • Types: reciprocating and rotary pumps
    • Characteristics: high pressure, low flow, positive delivery
    • Examples and applications