Turbomachinery (ME-603 (A)) - Important Questions

Derive the moment of momentum equation and Euler's turbine energy equation for turbomachines and give the expression for power / energy transfer, including for reaction and steam turbines.

Explain the term degree of reaction in turbomachinery / steam turbines, including 50% reaction turbine

Explain the application of the second law of thermodynamics to turbomachines.

Explain the application of the first law of thermodynamics to turbomachines.

Compare / relate the velocity diagrams of steam turbines and hydro turbines.

Explain velocity compounding and pressure compounding in steam turbines.

For a single-stage impulse turbine, construct inlet/outlet velocity triangles and calculate blade angles, whirl components, tangential and axial thrust, power/work developed and blading/diagram efficiency, with or without blade friction/velocity coefficient.

What is the reheat factor in multi-stage steam turbines and why does it give higher efficiency than a single stage with the same stage efficiency?

Derive the condition for maximum efficiency (blade speed ratio) of a reaction turbine stage.

Explain the various losses occurring in a turbine.

For a Parsons reaction turbine stage with given mean diameter, speed, steam velocity, outlet angle and mass flow, draw velocity diagram and determine blade inlet angle, tangential force and stage power.

Derive the expression for maximum blade (diagram) efficiency of a Parson's reaction steam turbine.

Derive the expression for optimum blade speed ratio for maximum blade efficiency of an impulse steam turbine.

In a single-stage impulse turbine given nozzle exit velocity, nozzle angle, blade angles and velocity coefficient, find the blade speed for shockless entry, stage efficiency and axial/end thrust.

Explain the factors affecting steam turbine performance and state the condition for maximum turbine efficiency.

Dry saturated steam is expanded in a nozzle from $1.3\ \text{MPa}$ to $0.1\ \text{MPa}$. Assume friction loss in the nozzle is equal to $10\%$ of the total enthalpy drop; calculate the mass of steam discharged when the nozzle exit diameter is $10\ \text{mm}$.

Draw the velocity diagram of an impulse steam turbine.

Numerically determine the power imparted to the runner (or available at the nozzle) and the hydraulic efficiency of a Pelton wheel from given head, discharge, bucket speed and jet deflection.

Explain the advantages of centrifugal pumps over reciprocating pumps.

Design calculation / numerical problem on a Pelton wheel for given head, speed, power and efficiencies.

Explain the construction and working of a Kaplan turbine, including its advantages and applications.

Explain the phenomenon of cavitation in water turbines.

Define and explain the various efficiencies (hydraulic, mechanical, volumetric and overall) of a hydraulic turbine.

Explain the classification of hydraulic turbines.

Calculate specific speed, power and identify type for a turbine given head, speed, discharge and efficiency.

Define and derive the expression for specific speed of a turbine.

With the help of neat sketch discuss the main parts of a centrifugal pump.

What is a draft tube? Explain the different types of draft tubes.

Define and derive the expression for specific speed of a pump.

Differentiate between / compare centrifugal flow compressor and axial flow compressor.

State and explain the Fan Laws and discuss their engineering applications.

Write short note on following- (Any Two):

Express fan efficiency $\eta$ as a function of dimensionless parameters formed from $\rho, \mu, \omega, D, Q$.

Describe the Polytropic efficiency of compressor.

Draw the vector diagram of centrifugal compressor.

Define surging and efficiency of an axial flow compressor.

Derive an expression for the degree of reaction of an axial flow compressor.

Draw and explain characteristic curves of fans.

Describe surging and choking in a compressor.

Explain vector diagram of axial flow compressor.

Explain the construction and working principle of a torque converter with the help of a neat diagram.

What is a hydraulic (fluid) coupling? Explain its working principle with the help of a neat sketch.

Write down the application of power transmitting devices at industry level.

Differentiate between a hydraulic intensifier and a hydraulic accumulator.

Explain with the help of a neat sketch the working principle of a hydraulic accumulator.

For a hydraulic press with given ram and plunger diameters and load, find the force required at the plunger.

What is positive displacement machines?

Draw a neat sketch of a torque converter.

What is a torque converter and where is it used?

What are Positive Displacement Pump?

Write short notes on any three of the following:

Describe second law of thermodynamic how it is related to boiler.

What is the role of entropy in the definition of second law of thermodynamics?

Write down the expression for equivalent evaporation for steam generator.

Describe any one type of boiler in detail.