Subject Code:ME601PC

DEPARTMENT OF MECHANICAL ENGINEERING III Year B. Tech., II-Sem.

Subject: THERMAL ENGINEERING-IINote: - All Questions are mapped with Blooms Taxonomy Levels and Course Outcomes.

UNIT-I2-MARKS QUESTIONS

S.No. Questions Skills CO P.I1 List and explain different processes in rankine cycle. Remember C321.1 2.2.3

2 List different methods to improve rankine cycle efficiency. Remember C321.1 2.2.3

3 Explain the concept of Mean temperature of heat addition Understand C321.1 1.4.1

4 Explain the operation of economizer with the help of simple diagram Understand C321.2 2.3.1

5 Define the term draught. State the difference between induced draught and forced draught Remember C321.2 2.3.1

3-MARKS QUESTIONSS.No. Questions Skills CO P.I

1 Classify boilers Analyze C321.2 2.3.1

2 Differentiate between water tube and fire tube boilers. Understand C321.2 2.3.4

3 Illustrate importance of boiler mountings and accessories. Apply C321.2 2.3.1

4 State the advantage of reheating. Explain reheat cycle with the help of T-s and h-s diagram Understand C321.1 2.2.3

5 Explain regenerative cycle with closed feed heater with the help of T-s diagram. Understand C321.1 2.2.3

5-MARKS QUESTIONSS.No. Questions Skills CO P.I

1 Derive an expression for the efficiency of rankine cycle. Create C321.1 2.4.4

2 Describe with neat sketch the lamont boiler Understand C321.2 2.3.1

3 In a steam power plant operating on an ideal Rankine cycle, the steam enters at 3 MPa and 400oC and is exhausted at 10 kPa. Assuming all ideal processes, determine the following:(a) Thermal efficiency of the cycle and heat supplied in the boiler. (b) Thermal efficiency if steam is bled from the turbine at a pressure of 0.1 MPa and is used to heat the feed water in an open feed water heater. Estimate the increase or decrease of efficiency for the regenerative cycle compared to simple and comment on the result of thermal efficiency and heat supplied in the boiler for both cases.

Evaluate

C321.1 1.4.1

4 A steam generator delivers steam at 100 bar, 500oC. The feed water inlet temperature is 160oC. The steam generation rate is

Apply C321.1 1.4.1

100,000 kg/hr and the steam generator efficiency is 88%. Determine: (i) Fuel burning rate in kg/h, if the calorific value of fuel is 21 MJ/kg. (ii) The percentage of total heat absorbed in the economizer, evaporator and super heater. Assume that only latent heat is absorbed in the evaporator and neglect any pressure drop.

5 Derive an expression for cycle efficiency of rankine cycle with single feed water heaters.

Create C321.1 1.4.1

Subject Code: ME601PC

DEPARTMENT OF MECHANICAL ENGINEERINGIII Year B. Tech., II-Sem.

Subject: THERMAL ENGINEERING-IINote: - All Questions are mapped with Blooms Taxonomy Levels and Course Outcomes.

UNIT-II2-MARKS QUESTIONS

S.No. Questions Skills CO P.I1 Describe the types of Nozzles. Understand C321.3 3.2.2

2 What is the effect of friction on the flow through a steam nozzle Remember C321.3 3.1.1

3 Derive the throat pressure expression for maximum discharge. Create C321.3 2.1.3

4In a steam nozzle steam expands from 4 bar to 1 bar. Initial velocity is 60 m/s and initial temperature is 200oC. Determine the exit velocity if the nozzle efficiency is 92%.

Apply C321.31.4.1

5 Summarize the assumptions of steam nozzles in thermodynamic analysis. Understand C321.3 2.3.2

3-MARKS QUESTIONSS.No. Questions Skills CO P.I

1 Explain the phenomenon of supersaturated flow in nozzle. Why and how it happens Understand C321.3

2

Steam enters a nozzle at a pressure of 2 MPa and 400oC with negligible approach velocity and leaves at a pressure of 3 bar. What is the shape of the nozzle? Assuming isentropic flow through nozzle, determine the exit diameter for a mass flow rate of 2.5 kg/s. (2M)

Apply C321.3

2.1.3

3

A steam turbine develops 190 kW with a steam consumption of 18 kg/kWh. The pressure and temperature of steam entering the nozzle are 12 bar and 250oC respectively. The steam leaves the nozzle at 1 bar. The diameter of the nozzle at the throat is 8mm. Calculate the number of nozzles used. If 10% of the enthalpy is lost due to friction in the diverging portion of the nozzle, determine the exit diameter.

Apply C321.3

2.1.3

4 Analyze effects of super saturation in a nozzle. Analyze C321.3 2.4.4

5 Define critical pressure ratio. Write the expression for critical pressure ratio in a steam nozzle. Understand C321.3 1.4.1

5-MARKS QUESTIONSS.No. Questions Skills CO P.I

1 Derive the conditions for discharge and its maximum value of a nozzle. Create C321.3 2.3.1

2 Explain the concept of Wilson line and represent it on h-s Diagram.

Understand C321.3 2.4.2

3 Steam is expanded in a set of nozzles from 10 bar and 250C to 5 bar. Predict type of nozzle is it .Assume the expansion to be isentropic.

ApplyC321.3 1.4.1

4 Explain the concept of discharge through the nozzle. Understand C321.3 2.3.1

5 Steam expands from 17 bar and 80°C superheat to 0 7 bar in a convergent-divergent nozzle. Assuming that the expansion is frictionless adiabatic, and the steam discharged is 025 kg/sec., calculate the diameters of the sections of nozzle (i) ata point where the pressure is 9-5 bar, and (ii) at exit.

Apply C321.3 2.1.3

Subject Code: ME601PC

DEPARTMENT OF MECHANICAL ENGINEERINGIII Year B. Tech., II-Sem.

Subject: THERMAL ENGINEERING-IINote: - All Questions are mapped with Blooms Taxonomy Levels and Course Outcomes.

UNIT-III2-MARKS QUESTIONS

S.No. Questions Skills CO P.I1 Explain “degree of reaction” in a steam turbine. Understand C321.4 2.4.2

2Explain the following terms for reaction turbines:(i) Diagram efficiency and (ii) Stage efficiency Understand C321.4 2.3.1

3 Explain Reheat factor. Understand C321.4 2.1.2

4 Describe bleeding of steam turbines. Understand C321.4 2.3.1

5 List the advantages of steam turbine over the steam engines. Remember C321.4 2.2.4

3-MARKS QUESTIONSS.No. Questions Skills CO P.I

1 Differentiate between impulse and reaction turbine Understand C321.4 5.2.1

2 Classify the steam turbines. Analyze C321.4

3 State the advantages and disadvantages of velocity compounded Impulse Turbine. Remember C321.4 7.1.1

4 Explain the concept of pressure compounding. with neat diagram Understand C321.4 3.1.6

5 Discuss the importance of compounding of steam turbine. Understand C321.4 2.3.1

5-MARKS QUESTIONSS.No. Questions Skills CO P.I

1 Explain velocity and pressure compounding with neat sketch. Understand C321.4 2.2.4

2 Draw the velocity diagram of impulse Turbine and solve for the work done on the blade, blade efficiency of turbine. Apply C321.4 1.4.1

3 Derive the expression for condition for maximum efficiency of an impulse Turbine? Create C321.4 1.4.1

4 Summarize the methods of reducing wheel or rotor speed Understand C321.4 2.2.3

5 Describe mechanical details of reaction turbines. Understand C321.4 2.3.1