ME-603-A Turbo Machinery - Jun 2026 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
   aDiscuss the application of the Second Law of Thermodynamics in the analysis of turbomachines.
   How to answer

   • Define Second Law - entropy, irreversibility, exergy concept
   • Application to turbomachines: isentropic vs actual processes
   • Efficiencies - isentropic, polytropic, exergy destruction
   • Example: compressor/turbine analysis with T-s diagram
2. 7 Marks
   bDerive the Moment of Momentum Equation for turbomachines and explain its significance.
   How to answer

   • State angular momentum principle for control volume
   • Derive Euler turbine equation: torque = mass flow times change in whirl
   • Steps: inlet/outlet velocity triangles, moment about axis
   • Significance: basis for work, head, degree of reaction
3. 7 Marks
   aDescribe Velocity and Pressure compounding of steam turbine.
   How to answer

   • Define compounding need in steam turbines
   • Velocity compounding: Curtis stage, nozzles, moving-fixed-moving blades, velocity diagram
   • Pressure compounding: Rateau, multiple stages pressure drop
   • Comparison with diagrams
4. 7 Marks
   bDerive the condition for maximum efficiency of a reaction stage.
   How to answer

   • Define reaction stage efficiency with velocity triangles and symmetric blading
   • Express efficiency as function of blade speed ratio $\rho = U/V_1$
   • Differentiate w.r.t $\rho$ and set to zero
   • Condition for maximum: $\rho = \cos \alpha_1$ for 50% reaction
5. 7 Marks
   aExplain the construction and working of a Kaplan turbine. Discuss its advantages and applications.
   How to answer

   • Construction: spiral casing, guide vanes, adjustable runner blades, draft tube
   • Working: axial flow, head range, blade pitch adjustment
   • Advantages: high efficiency at part load, low head
   • Applications: dams, irrigation, low-head hydel plants
6. 7 Marks
   bExplain the advantages of centrifugal pumps over reciprocating pumps.
   How to answer

   • Continuous vs intermittent flow, uniform delivery
   • No valves, less maintenance, handle impure fluids
   • High speed, compact, low cost
   • Comparison table on efficiency, head, priming
7. 14 Marks
   A Pelton wheel has a mean bucket speed of 10 metres per second with a jet of water flowing at the rate of 700 litres/s under a head of 30 metres. The buckets deflect the jet through an angle of $160^{\circ}$. Calculate (i) the power given by water to the runner and (ii) the hydraulic efficiency of the turbine. Assume co-efficient of velocity as 0.98
   How to answer

   • Calculate jet velocity $V_1 = C_v\sqrt{2gH}$
   • Runner power $P = \rho Q (V_1-U)(1-\cos\beta)U$
   • Hydraulic efficiency $\eta_h = P/(\rho g Q H)$
   • Substitute values and compute in kW and %
8. 7 Marks
   aDifferentiate between centrifugal flow and axial flow compressor.
   How to answer

   • Flow direction: radial vs axial, construction differences
   • Pressure ratio, mass flow, frontal area
   • Efficiency, speed, applications
   • Tabular comparison
9. 7 Marks
   bState and explain the Fan Laws. Discuss their engineering applications.
   How to answer

   • State Fan Laws: Q, H, P variation with N and D
   • Mathematical forms: $Q \propto N D^3$, $H \propto N^2 D^2$, $P \propto N^3 D^5$
   • Explanation with dimensional analysis
   • Engineering uses: scaling, speed control, testing
10. 7 Marks
    aExplain the construction and working a torque converter with the help of a neat diagram.
    How to answer

    • Components: pump impeller, turbine runner, stator with diagram
    • Working: fluid coupling with torque multiplication
    • Velocity/flow circulation explanation
    • Applications in automobiles
11. 7 Marks
    bDifferentiate between a hydraulic intensifier and a hydraulic accumulator.
    How to answer

    • Define hydraulic intensifier: pressure boosting, low to high pressure
    • Define hydraulic accumulator: energy storage, pressure stabilization
    • Differences in purpose, construction, operation
    • Applications of each
12. 14 Marks
    In a single-stage impulse turbine the nozzle discharges the hot gas on to the blades at a velocity of 750 m/s. The mass flow rate of gas is 100 kg/s. The turbine rotates at 20000 rpm. The mean diameter of wheel is 31.5 cm. The nozzles are inclined at an angle of $20^{\circ}$ to the plane of wheel rotation. Calculate- Assume the blade friction coefficient as 0.92 and outlet blade angle as $25^{\circ}$ to the plane of rotation.

    1. i)Power developed by the blades in MW.
    2. ii)Energy lost in the blades in MW, and
    3. iii)Determine the blade efficiency of the turbine.
    How to answer

    • Compute blade speed $U = \pi D N/60$
    • Inlet/outlet velocity triangles with $\alpha_1=20^{\circ}$, $K=0.92$
    • Power $P = \dot{m}U\Delta V_w$, loss = KE drop in relative velocity
    • Blade efficiency $\eta_b = 2U\Delta V_w/V_1^2$
13. 14 Marks
    Explain the following: (Any Two): (7x2=14)

    1. i)Degree of reaction of turbomachine
    2. ii)Surging in compressor
    3. iii)Draft tubes
    4. iv)Positive Displacement Pumps
    How to answer

    • Degree of reaction: definition, formula, impulse vs reaction
    • Surging: cause, cycle, effects and prevention
    • Draft tube: purpose, types, efficiency gain
    • Positive displacement pumps: types, working, uses