THERMODYNAMIC CYCLES ANNA UNIVERSITY Question Bank

DEPARTMENT OF MECHANICAL ENGINEERING
THERMODYNAMIC CYCLES QUESTION BANK 
ANNA UNIVERSITY Question Bank
Sub. Code/Name:
THERMODYNAMIC CYCLES
Part-A (2 Marks)
1. What is a thermodynamic cycle?
2. What is meant by air standard cycle?
3.. Name the various “gas power cycles".
4. What are the assumptions made for air standard cycle analysis
5. Mention the various processes of the Otto cycle.
.
6. Mention the various processes of diesel cycle.
7. Mention the various processes of dual cycle.
9. Define air standard cycle efficiency.
10. Define mean effective pressure as applied to gas power cycles. How it is related to indicate power
of an I.C engine?
11. Define the following terms. (i) Compression ratio (ii) Cut off ratio , (iii) .Expansion ratio
Part-B (16Marks)
1. Drive and expression for the air standard efficiency of Otto cycle in terms of volume ratio. (16)
2. Drive an expression for the air standard efficiency of Diesel cycle. . (16)
3. Drive an expression for the air standard efficiency of Dual cycle. . (16)
4. Explain the working of 4 stroke cycle Diesel engine. Draw the theoretical and actual PV diagram.
5. Drive the expression for air standard efficiency of Brayton cycle in terms of pressure ratio (16)
6. A Dual combustion air standard cycle has a compression ratio of 10. The constant pressure part of
combustion takes place at 40 bar. The highest and the lowest temperature of the cycle are 1725
degree C and 27 0 C respectively. The pressure at the beginning of compression is 1 bar.
Calculate (I) the pressure and temperature at’ key points of the cycle. (ii) The heat supplied at
ME2301 THERMAL ENGINEERING
Rajalakshmi Engineering College
Thermal Engineering
2
constant volume, (iii) the heat supplied at constant pressure. (Iv) The heat rejected. (v) the work
output. (vi) the efficiency and (vii) mep. (16)
7. An Engine-working on Otto cycle has a volume of 0.45 m3 , pressure 1 bar and temperature 30o,C
at the beginning of compression stroke. At the end of compression stroke, the pressure is 11 bar
and 210 KJ of heat is added at constant volume. Determine (i) Pressure, temperature and volumes
at salient points in the cycle.' (ii) Efficiency. (16)
8. (I)Explain the working of 4-stroke cycle Diesel engine. Draw the theoretical and actual valve- timing
diagram for the engine. explain the reasons for the difference.
9. (II) Air enters the compressor of a gas turbine at 100 KPa and 25 o C. For a pressure ratio of 5 and
a maximum temperature of 850°C. Determine the thermal efficiency using the Brayton cycle.
(16)
The following data in referred for an air standard diesel cycle compression ratio = 15 heat added
= 200 Kj/Kg- minimum temperature in the cycle = 25°C Suction pressure = 1 bar Calculate
1. Pressure and temperature at the Salient point.
2. Thermal efficiency
3. Mean effective pressure,
4. Power output of the cycle If flow rate 'of air is 2 Kg/s (16)
I.C ENGINE
Part-A (2 Marks)
01. Classify IC engine according to cycle of lubrication system and field of application.
Types of lubrication system
02. List the various components of IC engines.
03. Name the basic thermodynamic cycles of the two types of internal combustion reciprocating
engines.
04. Mention the important requites of liner material.
05. State the purpose of providing piston in IC engines.
06. Define the terms as applied to reciprocating I.C. engines "Mean effective pressure" and
"Compression ratio".
07. What is meant by highest useful compression ratio?
08. What are the types of piston rings?
09. What is the use of connecting rod?
.
10. What is the use of flywheel?
Thermal Engineering
3
Part-B (16Marks)
1. Explain full pressure lubrication system I.C Engine . (16)
2. Explain the water cooling system in I.C Engine . (16)
3. Explain the 2 types of Ignition system In 5.1 Engine . (16)
4. Draw and explain the valve timing diagram of 4 stroke Diesel Engine . (16)
5. Draw and explain the port timing diagram of 2stroke Petrol Engine . (16)
6. Explain with neat sketch the exhaust gas analysis . (16)
7. The following results refer to a test on a petrol engine Indicated power = 30 Kw, Brake power = 26 Kw
Engine speed = 1000 rpm
Fuel brake power/ hour = 0.35 kg
Calorific value of fuel = 43900kj/kg
Calculate The indicated Thermal efficiency
The brakeThermal efficiency
The Mechanical efficiency (16)
8. A four cylinder 2 stroke cycle petrol engine develops 23.5 kw brake power at 2500 rpm. The mean
effective pressure on each piston in 8. 5 bar and mechanical efficiency in 85% Calculate the diameter
and stroke of each cylinder assuming the length of stroke equal to 1.5 times the diameter of cylinder.
(16)
9. The following data to a particular twin cylinder two stroke diesel engine. Bore 15 cm stroke. 20 cm.
speed 400 rpm. Indicated mean effective pressure 4 bar, dead weight on the brake drum 650 N. spring
balance reading 25 N Diameter of the brake drum 1 m .Fuel consumption 0.075 kg/min and calorific
value of the fuel is 44500 kj/J kg.
Determine
1. Indicated Power
2. Brake Power
3. Mechanical efficiency
4. Indicated thermal efficiency
5. Brake thermal efficiency (16)
UNIT-3 STEAM NOZZLE&TURBINE
Part-A (2 Marks)
01. What are the various types of nozzles and their functions?
02. Define nozzle efficiency and critical pressure ratio.
STEAM NOZZLES AND TURBINES
Thermal Engineering
4
03. Explain the phenomenon of super saturated expansion in steam nozzle. or What is metastable
flow?
04. State the function of fixed blades.
05. Classify steam turbines.
06. How does impulse work?
07. What is meant by carry over loss?
08. State the function of moving blades...."
09. What is the fundamental difference between the operation of impulse and reaction steam turbines?
10. What are the different methods of governing steam turbines?
11. How is throttle governing done?
12. Where nozzle control governing is used?
13.. Where by - pass governing is more suitable?
14. What are the different losses in steam turbines?
PART- B (16Marks)
1. An impulse turbine having a set of 16 nozzles receives steam at 20 bar, 400° C. The pressure of
steam at exist is 12 bar. if the total discharge Is 260 Kg/min and nozzle efficiency is 90% . Find the cross
sectional area of each nozzle, if the steam has velocity of 80m/s at entry to the nozzle, find the
percentage Increase In discharge. (16)
2. Dry saturated steam at a pressure of 8 bar enters the convergent divergent nozzle and leaves it at a
pressure 1.5 bar. If the flow isentropic and if the corresponding index of expansion is 1.133, find the ratio
of 0.3 are at exit and throat for max. discharge. (16)
3. Steam enters a group of nozzles of a steam turbine at 12 bar and 2200 C and leaves at 1.2 bar. The
steam turbine develops 220 Kw with a specific steam consumption of 13.5 Kg/ Kw. Hr. If the diameter of
nozzle at throat Is 7mm . Calculate the number of nozzle (16)
4. Drive an expression for critical pressure ratio in terms of the index of expansion (16)
5. Explain the method of governing in steam turbine. (16)
6. Explain various type of compounding in Turbine (16)
Thermal Engineering
5
7. A 50% reaction turbine running at 400 rpm has the exit angle of blades as 20° and the velocity of
steam relative to the blade at the exit is 1.35 times mean speed of the blade. The steam flow rate is
8.33 kg/s and at a particular stage the specific volume is 1.38m3/kg .Calculate, suitable blade
height, assuming the rotor mean diameter 12 times the blade height, and diagram work. (16)
8. The blade angle of a single ring of an impulse turbine is 300m/s and the nozzle angle is 200.The
isentropic heat drop is 473kJ/kg and nozzle efficiency is 85%.Given the blade velocity coefficient is 0.7
and the blades are symmetrical, Draw the velocity diagram and calculate for a mass flow of 1 kg/s i)
axial thrust on balding ii) steam consumption per BP hour if the mechanical efficiency is 90% iii) blade
efficiency and stage efficiency. (16)
AIR COMPRESSORS
Part-A (2 Marks)
01. What is meant by single acting compressor?
02.What is meant by double acting compressor?
03. What is meant by single stage compressor?
04. What is meant hy multistage compressor?
05. Define isentropic efficiency
06. Define mean effective pressure. How is it related to in power of an I.C engine.
07. What is meant by free air delivered?
08. Explain how flow of air is controlled in a reciprocating compressor?
09. What factors limit the delivery pressure in reciprocating compressor?
10. Name the methods adopted for increasing isothermal efficiency of reciprocating air compressor.
11. Why clearance is necessary and what is its effect on the performance of reciprocating compressor?
12. What is compression ratio?
13. What is meant by inter cooler?
Part-B (16 Marks)
1. Drive an expression for the work done by single stage single acting reciprocating air compressor.
(16)
2. Drive an expression for the volumetric efficiency of reciprocating air compressors (16)
Thermal Engineering
6
3. Explain the construction and working of a root blower (16)
.
4. Explain the construction and working of a centrifugal compressor (16)
5. Explain the construction and working of a sliding vane compressor and axial flow compressor(16)
6. A single stage single acting air compressor is used to compress air from 1 bar and 22° C to 6 bar
according to the law PV1 .25 = C. The compressor runs at 125 rpm and the ratio of stroke length to bore of
a cylinder is 1.5. If the power required by the compressor is 20 kW, determine the size of the cylinder .
(16)
7. A single stage single acting air compressor is used to compress air from 1.013 bar and 25° C to 7 bar
according to law PV 1.3 = C.The bore and stroke of a cylinder are 120mm and 150mm respectively. The
compressor runs at 250 rpm .If clearance volume of the cylinder is 5% of stroke volume and the
mechanical efficiency of the compressor is 85%, determine volumetric efficiency, power, and mass of air
delivered per minute. (16)
8. A two stage singe acting air compressor compresses 2m3 airs from 1 bar and 20° C to 15 bar. The air
from the low pressure compressor is cooled to 25° C in the intercooler. Calculate the minimum power
required to run the compressor if the compression follows PV1.25=C and the compressor runs at 400
rpm. (16)
REFRIGERATION AND AIR CONDITIONING
Part-A (2 Marks)
01. Name four important properties of a good refrigerant
02. What is the difference between air conditioning and refrigeration?
03. What is the function of the throttling valve in vapour compression refrigeration system?
04. In a vapour compression refrigeration system, where the highest temperature will occur?
05. The vapour absorption system can use low-grade heat energy in the generator. Is true of false?
06. Name any four commonly used refrigerants.
07. Explain unit of Refrigeration.
08. Why throttle valve is used in place of expansion cylinder for vapour compression refrigerant
machine.
Thermal Engineering
7
09. What are the effect pf super heat and suhcooling on .the vapour compression cycle?
10. What are the properties of good refrigerant?
11. How are air-conditioning systems classified?
12. How does humidity affect human comfort?
13.. What are the various sources of heat gain of an air-conditioned space?
14. What do you mean by the term infiltration in heat load calculations?
Part-B (16 Marks)
1. Draw neat sketch of simple vapor compression refrigeration system and explain. (16)
2. Explain with sketch the working principle of aqua Ammonia refrigeration system. (16)
3. Explain with sketch the working principle of water-Lithium bromide refrigeration system. (16)
4. Briefly explain the cooling load calculation in air conditioning system. (16)
5. Explain winter, summer, and year round Alc system. (16)
6. Explain unitary Alc and central Alc system. (16)
7. Explain any four psychometric processes with sketch. (16)
8. A refrigeration system of 10.5 tonnes capacity at an evaporator temperature of -12°C and a condenser
temperature of 27°C is needed in a food storage locker. The refrigerant Ammonia is sub cooled by
6°C before entering the expansion valve. The compression in the compressor is of adiabatic type.
Find 1. Condition of vapor at outlet of the compressor.2. Condition of vapor at the entrance of the
Evaporator 3.COP &power required. (16)
9. A sling psychrometer in a lab test recorded the following readings DBT=35°C,WBT=25°C
Calculate the following
1. Specific humidity
2. Relative humidity
3. Vapor density in air
4. Dew point temperature
5. Enthalpy of mixing per kg of air .take atmospheric pressure=1.0132 bar. (16)

CY1201 PRINCIPLES OF ENVIRONMENTAL SCIENCE & ENGINEERING QUESSTION BANK DOWNLOAD

PRINCIPLES OF ENVIRONMENTAL SCIENCE & ENGINEERING (CY 1201) QUESSTION BANK DOWNLOAD
PRINCIPLES OF ENVIRONMENTAL SCIENCE & ENGINEERING (CY 1201) QUESSTION BANK DOWNLOAD
ANNA UNIVERSITY QUESTION BANK


UNIT – 3


PART – A


1. Define Environmental studies.
2. What are the principles of environmental education?
3. Mention the scope and importance of Environmental studies.
4. How forests are useful to mankind?
5. What is mining? Mention the methods of mining.
6. Enumerate the effects of mining on the environment.
7. What are Dams? How is it useful to human beings?
8. Discuss the problems of over-exploitation of Ground water.
9. What are the methods of flood control?
10. What are the up-stream impacts of constsruction of dams?
11. Define under-nutrition & mal-nutrition.
12. What are the merits of using renewable energy resources?
13. Why alternate energy resources are required?
14. What is the application of wind energy?
15. Write a note on Geo-Thermal energy.
16. What is soil erosion?
17. Differentiate between renewable & non-renewable energy resources.
18. Mention the advantages & disadvantages of modern agriculture.
19. Differentiate between organic and synthetic fertilizers.
20. What is an aquifer? Mention its types.
21. What are the types of mining?
22. Mention the types of drought.
23. What are super-pests?
24. Define Eutrophication.
25. What is biological magnification?
26. What is organic farming?
27. What is meant by sustainable development?
28. What are the major causes of deforestation?
29. Mention the effects of ground water usage?
30. What are the types of minerals?
31. What is microbial leaching technique?
32. What is carrying capacity?
33. What are the types of soil erosion?
34. What are the uses of various types of minerals?
35. What is bio-gas?
36. What is nuclear energy?
37. Define sustainabe forestry.
38. State the environmental effects of extracting & using mineral resources.
39. State the need for public awareness for solving environmental problems.
40. What is water logging?
41. What is salinization?




PART – B


1. What are conventional energy resources? Discuss about solar energy and Ocean thermal energy.
2. Discuss the major causes & consequences of deforestation?
3. Explain the major impacts of timber extraction and mining.
4. Enumerate the various benefits and drawbacks of constructing dams.
5. What are the uses and over-exploitation of water? Explain with a case-study.
6. Comment on floods & drought.
7. What are the environmental impacts of mineral extraction? Explain.
8. Discuss in detail the impacts of over-grazing & agriculture.
9. Write short notes of (i) Tidal energy (ii) Bio-gas (iii) Nuclear energy.
10. Explain the various types of land degradation.
11. Explain as an individual how will you conserve natural resources.
12. How will you achieve sustainable life-style by equitable share of resources.
13. What are the measures recommended for conservation of natural resources.
14. Explain briefly the various methods of harvesting solar energy.
15. Explain in detail the effects due to pesticides usage in moderns agriculture.




UNIT-1


PART-A


1. Define Ecology?
2. Define Eco-System with an example?
3. What are the structural components of an Ecosystem?
4. Bring out the functional features of an Ecosystem?
5. Differentiate between Food Chain and Food Web?
6. What are Ecological Pyramids. Give examples.
7. Pyramid of energy is always upright. Explain.
8. What are Biochemical cycles. Explain their importance?
9. What is the significance of Ecological pyramids?
10. There found to be only 4 to 5 trophic levels in any Ecosystem. Explain.
11. What is Ecological Succession. Mention its types.
12. Discuss about the prime characteristics of
a.Forest Ecosystem
b.Grassland Ecosystem
c.Desert Ecosystem
d.Aquatic Ecosystem
13. Differentiate species and genera. (or) Define genetic diversity.
14. Differentiate between biodiversity and ecosystem biodiversity.
15. What are hotspots of biodiversity?
16. Justify India to be a great spot of biodiversity.
17. Bring out the threats towards biodiversity .How poaching affects biodiversity.
18. Define Endemism with an example.
19. What are endangered species? Give examples.
20. What are the aesthetic values of biodiversity.
21. What are National Parks. Name few parks in India.
22. Explain the necessity to conserve biodiversity.
23. What are GPP and NPP.
24. What is Ecological regulators.
25. Define Food Chain with an example.
26. Define Food Web with an example.
27. Discuss the water cycle.
28. Bring few methods to conserve biodiversity.
29. What is stratification?
30. Bring out the classification of aquatic ecosystem.
31. Explain ecological; pyramids with respect to pond ecosystem.
32. What is ecosystem diversity.
33. Bring out the Bio-geographical classification of India.
34. Comment on local or regional biodiversity.
35. Explain Endemism with respect to India.
36. Bring out the order of distribution of biodiversity through out the world with reasons.
37. What is biodiversity and its significance.
38. Explain biosphere.
39. Explain threatened species.






PART-B


1. Explain the components, characteristics and biodiversity of Forest ecosystem.
2. Explain the structure and functional features of Aquatic ecosystem.
3. Discuss in detail about Ecological succession stating the various stages.
4. What are trophic levels? Explain the flow of energy and minerals in ecosystem.
5. Explain the two models of energy flow in an ecosystem.
6. Discuss the value of biodiversity.
7. Explain Carbon and Nitrogen cycles.
8. Explain the Sulphur and Phosphorus cycles.
9. What are the threats faced by biodiversity. What are the solutions for the threats.
10. Explain In-situ and Ex-situ conservation of biodiversity.(or) What are the measures recommended for conservation of biodiversity.
UNIT-2


PART-A


1. Define Pollution.
2. What are the types of pollutants.
3. What are the types of Air pollutants.
4. What is suspended particulate matter. Give example.
5. Define photochemical smog.
6. What are types of acid rain.
7. How will you control air pollution.
8. Give the major water pollutants with example.
9. What is meant by point and nonpoint sources.
10. What is chlorosis and necrosis.
11. What is bioaccumulation.
12. Mention the diseases caused by nitrates.
13. Define BOD and COD.
14. Define soil pollution.
15. What are the sources of soil pollution.
16. What are the sources effects of marine pollution.
17. What are the control methods of thermal pollution.
18. Give the sources of radio activity.
19. Classify solid wastes.
20. What are the sources of urban and industrial wastes.
21. Why do earth quake occur.
22. What are the damages caused by io0nic radiations.
23. What are the various types of natural disasters.
24. What are the roles of a citizen in reducing pollution.
25. What are Municipal Solid Wastes(MSW)
26. What is composting.
27. What is incinerators.
28. What are aerosols. Give examples.
29. Explain aerobic and anaerobic oxidation.
30. What are the two main commonly used radio isotopes in nuclear fission reactions?
31. Explain disaster management briefly.
32. What is meant by automobile pollution.
33. What is domestic sewage?
34. What are the sources and effects of air pollutants.
35. Define thermal pollution.


PART- B


1.Mention the sources and effects of various air pollutants.
2. Describe the method of control of air pollution.
3.Briefly describe the sources effects and control of noise pollution.
4. Enumerate with example the major sources of surface and ground water
pollution.
5. Wrtie short notes on a) Minimata disease b) blue baby syndrome c) itai-itai
disease.
6. Explain the method of sewage water treatment.
7. What are the major sources of soil pollution?
8. What are the measures to be taken to prevent soil pollution?
9. Explain in detail the Solid waste management techniques.
10. Write notes on (i) Floods (ii) Landslides (iii) Cyclones.
11. Explain any two case studies on Nuclear pollution.
12. What are the sources, effects & control measures of Marine pollution?
13. Explain the various types of Radio-active radiations.
14. Explain the causes,effects & control measures of Water pollution.
15.What are the effects of improper municipal solid waste management? State
the measures recommended for proper management of the solid waste.
16.Explain the methods of disposal of municipal solid waste.
17.Write notes on disposal of radio-active wastes.
18.Compare the nuclear power with coal power.
19.What are the causes of soil erosion and methods of preventing it.
20.Discuss the aspects of prevention & control of noise.




UNIT – 4


PART – A


1. Define Sustainable development.
2. Write a note on Earth Summit – 1992.
3. Bring out the important aspects of sustainable development.
4. Write a note on 3R principle.
5. Define Rain Water Harvesting.
6. What are the objectives of rain water harvesting?
7. What is water Shed?
8. What are the objectives (or) principles of watershed management?
9. Write a note on agro-forestry.
10. Name few Green-House gases.
11. What are the effects of global warming?
12. Mention few practices to reduce global warming.
13. Explain acid-rain and its effects.
14. Bring out the reactions taking place at stratosphere.
15. What are the effects of Ozone-Layer depletion?
16. Compare Consumerism & Waste generation.
17. Enlist the factors affecting the sustainable society.
18. Differentiate between Re-habilitation & Re-settlement of people.
19. Mention the objectives of Environment Protection Act.
20. Enlist the objectives of Air-Pollution Act.
21. Explain the Wild-Life protection Act.
22. Explain the necessity of Environmental Legislation.
23. What is nuclear holocaust? How can it occur?
24. Write a note on crop rotation.
25. Discuss the articles 48-A & 51-A of Indian Constitutional provision for Environmental protection.
26. Write a note on CPCB & SPCB.
27. Indicate some methods to create environmental awareness among public.
28. How can we achieve the goal of sustainable development?
29. Define environmental ethics.
30. How does a climate change occur?
31. Mention any two control measures on acid rain.
32. What is acid deposition ?
33. Define population explosion.


PART – B


1. Bring out the activities of NGO’s on environmental protection.
2. Discuss about the Forest Act, 1980 and its amendment –1992.
3. Describe about Water Act – 1974.
4. Describe the important waste land reclamation practices.
5. Describe environmental ethics in detail.
6. Discuss the modern techniques of rain water harvesting.
7. Discuss the water shed management practices.
8. Discuss in detail about the water conservation methods.
9. Discuss the agenda for sustainable development.
10. Write in detail about global warming.
11. Explain the mechanism of Ozone layer depletion.
12. Write briefly on community participation in environment management programmes.
13. Discuss briefly of the Indian environmental Acts.
14. Write short notes on a) environmental ethics b) waste land reclamation.
15. State the important provisions in Environment protection Act , Air Act Water Act.


UNIT – 5


PART –A


1. Write short notes on population dynamics.
2. What are the factors affecting population size?
3. What is meant by population stabilization.
4. Define the term population explosion.
5. What kinds of problems are created due to Urbanisation?
6. What are the objectives of Family Planning Programmes?
7. Mention the types of health hazards with examples.
8. What is the role of primary health care against AIDS?
9. What do you mean by remote sensing?
10. Mention the applications of remote sensing on water resources.
11. What is doubling time, total fertility rates?
12. Define Zero Population growth.
13. What are the two important views of population growth?
14. What is meant by value education?
15. What is GIS?
16. Define (i) Toxins (ii) Carcinogens (iii) Tetrogenic (iv) Neurotoxins.
17. State how environment & human health are related?


PART – B


1. Explain the population characteristics & variations among nations.
2. What is meant by population explosion? Discuss the Indian Scenario.
3. What is meant by population stabilization? Discuss the family welfare and family planning in Indian context.
4. Discuss the influence of environmental parameters and pollution on human health.
5. What is Universal declaration of Human rights? What is its importance in achieving the goals of equity, justice & sustainability.
6. Discuss the salient features of Draft declaration of Human Rights on environment.
7. What are the objectives & elements of Value-education? How can the same be achieved?
8. Briefly discuss HIV/AIDS, mode of its spread and its effect on environment.
9. Discuss various issues & measures for Women & Child Welfare at International & National level.
10. What is the role of NMIS, ENVIS & GIS in dissemination of environmental information and environmental management?
11. Explain the role of Information Technology in environment & Human health.
12. Discuss the environmental and social impacts of growing population.
13. Write briefly on the effect of increasing affluence on environment.
14. Write briefly on implementation of family planning programme.
15. Write a note on AIDS in developing countries.
16. Discuss the factors influencing the family size.

EE1213 ELECTRIC DRIVES AND CONTROL ANNA UNIVERSITY QUESTION BANK

EE 1213 ELECTRIC DRIVES AND CONTROL(131305) QUESTION BANK
ELECTRIC DRIVES AND CONTROL(131305)  ANNA UNIVERSITY QUESTION BANK DOWNLOAD
PART A


1. What is meant by electrical drive?


2. Draw the block diagram of an electrical drive system.


3. Draw the mechanical characteristics of DC series motor.


4. Define plugging in three phase induction motor.


5. Why a starter is necessary for a DC motor?


6. Name the various types of starters commonly used for starting an induction motor.


7. What is static Ward-Leonard drive?


8. State the advantages of DC chopper drives.


9. Mention some of the merits and demerits of AC drives.


10. What is meant by v/f control?


11. Explain about OLR coil


12. Mention different types of three phase motor starters.


13. Mention the factors affecting the speed of a DC motor.


14. State the advantages of flux control method.


15. List the various advantages of DC Chopper.


16. Bring out the starting current equation and explain how it
Reaches the very high value.


17. What is the need of NVC in starter?


18. Draw the general block diagram of starter circuit.


19. List the various methods of controlling speed of DC shunt
Motor.


20. What do you mean by controlled rectifier?



PART B


1. Explain different types of electric drives and its applications to
Industry.


2. What are the different classes of motor duty and explain in detail?


3. What are the different electrical braking methods used in electrical
Drives? Explain any one method applied to DC shunt motor.


4. Draw and explain the torque – speed characteristics of three phase induction motor with necessary equation.


5. Describe the principle of starting of DC shunt motor using power and
Control circuit with neat circuit diagram.


6. What do you understand by the term soft start? Explain the soft start
Method employed for induction motor?


7. Discuss in brief various conventional methods of speed control of DC motors.


8. Draw and explain some of the commonly used controlled rectifier circuits for DC drive.


9. Explain the method of control of three phase induction motor by


(i) Stator voltage control


(ii) Frequency control


10. Explain with neat sketch the static Kramer variable speed drive system used for slip power recovery.


11. List out the types of starters utilized for three phase squirrel
cage induction motor.


12. What type of starter used in three phase slip ring induction
motor?


13. What is a controlled rectifier and how the concept is
Implemented in DC choppers and mentions its advantages.


14. Explain briefly about typical starting control circuits of DC shunt and
Series motors.


15. Explain neatly about the types of speed control methods in DC shunt
Motors.


16. Draw and explain neatly about the four types of flux control process in
DC series Motor.

ME1202 Fluid Mechanics and Machinery QUESTION BANK DOWNLOAD

ME1202 Fluid Mechanics and Machinery QUESTION BANK DOWNLOAD
ANNA UNIVERSITY MECHANICAL ENGINEERING QUESTION BANK
Fluid Mechanics and Machinery 113303 QUESTION BANK DOWNLOAD


                                                            Part A
Unit 1

   1. Define fluid.
   2. Differentiate between fluid and solid.
   3.  Define Specific volume
   4. Define Specific gravity.
   5. Define Viscosity.
   6. Define Compressibility.
   7. Define vapour pressure.
   8. Define Capillarity.
   9. Define Surface tension.
  10. Differentiate between Absolute and gauge pressures.
  11. Mention two pressure measuring instruments.
  12. What is peizometer?
  13. How manometers are classified.
  14. What is pitot static tube?
  15. Write down the units for dynamic and kinematic viscosity.
  16. State Newton’s law of viscosity.
  17. Differentiate between Newtonian and non Newtonian fluid.
  18. Differentiate between ideal and real fluid.
  19. What is ideal plastic fluid?
  20. Define velocity gradient.
  21. What is the difference weight density and mass density?
  22. What is the difference between dynamic and kinematic viscosity?
  23. Differentiate between specific weight and specific volume.
  24. Define relative density.
  25. What is vacuum pressure?
  26. What is absolute zero pressure?
  27. Write down the value of atmospheric pressure head in terms of water and Hg.
  28. Define stream line.
  29. Define path line.
  30. Define streak line.
  31. Define steady flow.
  32. Define uniform flow.
  33. Differentiate between laminar and turbulent flow.
  34. How will you classify the flow as laminar and turbulent?
  35. Differentiate between compressible and incompressible flow.
  36.  Differentiate between rotational and irrotational flow.
  37. Define stream function.
  38. Define velocity potential function.
  39. Write down continuity equation for compressible and incompressible fluid.
  40. Write down continuity equation in three dimensions.

FORM NO. CF14

  41. Differentiate between local and convective acceleration.
  42. Define circulation.
  43. Define flow net.
  44. Write down Euler’s equation of motion.
  45. Write down Bernoulli’s equation of motion for ideal and real fluid.
  46. State the assumptions made in Bernoulli’s equation of motion.
  47. Mention the applications of Bernoulli’s equation of motion.
  48. Mention  few discharge measuring devices
  49. Draw the venturimeter and mention the parts.
  50. Why the divergent cone is longer than convergent cone in venturimeter?
  51. Compare the merits and demerits of venturimeter with orifice meter.
  52. Why Cd value is high in venturimeter than orifice meter?
  53. What is the difference between Pitot tube and Pitot static tube?
  54. What is orifice plate?
  55. What do you mean by vena contracta?
  56. Define coefficient of discharge.
  57. Define coefficient of velocity.
  58. Define coefficient of contraction.
  59. State Buckingham’s Pi Theorem.
  60. What is dimensional homogeneity?
  61. What is dimensionless number?
  62. Mention the methods for dimensional analysis.
  63. Mention few important dimensionless numbers.
  64. Mention the type of forces acting in moving fluid.
  65. Define Reynold’s number.
  66. Define Froude’s number.
  67. Define Euler’s number.
  68. Define Weber’s number.
  69. Define Mach’s number.
  70. What is the difference between model and prototype?
  71. Mention two application of similarity laws
  72. Define geometric similarity.
  73. Define kinematic similarity.
  74. Define dynamic similarity.
  75. What is the difference between fluid kinematics and fluid dynamics?
  76. Write down Hagen poiseulle's equation
  77. Sketch the velocity distribution for laminar flow between parallel plates.
  78. Sketch the shear stress distribution for laminar flow between parallel plates
  79. Differentiate between Hydraulic Gradient line and Total Energy line.
  80. Write down Darcy -weisback's equation.
  81. Mention the application of moody diagram.
  82. What is the difference between friction factor and coefficient of friction?
  83. What do you mean by major energy loss?
  84. List down the type of minor energy losses.

  85. What is compound pipe?
  86. What do you mean by equivalent pipe?
  87. What is the condition for maximum efficiency of power transmission?
  88. Define boundary layer thickness.
  89. What do you mean by boundary layer separation?
  90. Define displacement thickness.
  91. Define energy thickness.
  92. Define momentum thickness.
  93. How boundary layers are classified?
  94. Define laminar boundary layer
  95. Define turbulent boundary layer.
  96. Define laminar sub layer.
  97. On what basis, the boundary layer is classified as laminar and turbulent?
  98. Define drag force.
  99. Define lift force.  
 100.  Define turbine.

 101. What are the classifications of turbine
 102. Define impulse turbine.
 103. Define reaction turbine.
 104. Differentiate between impulse and reaction turbine.
 105. What is the function of draft tube?
 106. Define specific speed of turbine.
 107. What are the main parameters in designing a Pelton wheel turbine?
 108. What is breaking jet in Pelton wheel turbine?
 109. What is the function of casing in Pelton turbine
 110. Draw a simple sketch of Pelton wheel bucket.
 111. What is the function of surge tank fixed to penstock in Pelton turbine?
 112. How the inlet discharge is controlled in Pelton turbine?
 113. What is water hammer?
 114. What do you mean by head race?
 115. What do you mean by tail race?
 116. What is speed ratio?
 117. What is flow ratio?
 118. What is the difference between propeller and Kaplan turbine?
 119. Mention the parts of Kaplan turbine.
 120. Differentiate between inward and outward flow reaction turbine.
 121. What is the difference between Francis turbine and Modern Francis turbine?
 122. What is the difference between outward and inward flow turbine?
 123. What is mixed flow reaction turbine? Give an example.
 124. Why draft tube is not required in impulse turbine?
 125. How turbines are classified based on head. Give example.
 126. How turbines are classified based on flow. Give example
 127. How turbines are classified based on working principle. Give example.
 128. What does velocity triangle indicates?


129.       Draw the velocity triangle for radial flow reaction turbine.
130.       Draw the velocity triangle for tangential flow turbine.
131.       Mention the type of characteristic curves for turbines.
132.       How performance characteristic curves are drawn for turbine.
133.       Mention the types of efficiencies calculated for turbine.
134.       Define Hydraulic efficiency
135.       Define Mechanical efficiency.
136.       Define overall efficiency.
137.       Define pump.
138.       How pumps are classified?
139.       Differentiate pump and turbine.
140.       Define Rotodynamic pump.
141.       Define Positive displacement pump.
142.       Differentiate between Rotodynamic and positive displacement pump.
143.       Define cavitation in pump.
144.       What is the need for priming in pump?
145.       Give examples for Rotodynamic pump
146.       Give examples for Positive displacement pump.
147.       Mention the parts of centrifugal pump.
148.       Mention the type of casing used in centrifugal pump.
149.       Why the foot valve is fitted with strainer?
150.       Why the foot valve is a non return type valve?
151.       Differentiate between volute casing and vortex casing.
152.       What is the function of volute casing?
153.       What is the function of guide vanes?
154.       Why the vanes are curved radially backward?
155.       What do you mean by relative velocity?
156.       What is whirl velocity?
157.       What do you mean by absolute velocity?
158.       What is the function of impeller?
159.       Mention the types of impeller used.
160.       Mention the types of efficiencies calculated for pump.
161.       Define Hydraulic efficiency
162.       Define Mechanical efficiency.
163.       Define overall efficiency
164.       Define specific speed of pump.
165.       Mention the type of characteristic curves for pump
166.       How performance characteristic curves are drawn for pump.
167.       Mention the parts of reciprocating pump.
168.       What is the function of air vessel?
169.       What is slip of reciprocating pump?
170.       What is negative slip?
171.       What is the condition for occurrence of negative slip?
172.       What does indicator diagram indicates?
173.       What is the difference between actual and ideal indicator diagram?


174.       Briefly explain Gear pump.
175.       Differentiate between internal gear pump and external gear pump.
176.       Briefly explain vane pump.
177.       What is rotary pump?
178.       Draw the velocity triangle for centrifugal pump.
179.       Draw the indicator diagram fro reciprocating pump.
180.       What is the amount of work saved by air vessel?
181.       Mention the merits and demerits of centrifugal pump.
182.       Mention the merits and demerits of reciprocating pump.
183.       What is separation in reciprocating pump?
184.       How separation occurs in reciprocating pump?
185.       Write down the equation for loss of head due to acceleration in reciprocating  
           pump.
186.       Write down the equation for loss of head due to friction in reciprocating pump.
187.       Differentiate single acting and double acting reciprocating pump.

Part B QUESTIONS (Theory / Derivation)

1.      Derive continuity equation in three dimension
2.      Derive Bernoulli’s equation from Euler’s equation of motion.
3.      Derive an expression for discharge in venturimeter
4.      Derive an expression for discharge in orifice meter
5.      Derive Hagen poisuielle’s equation for laminar flow through circular pipe.
6.      Derive Darcy-weisback equation for flow through pipes
7.      Explain the types of similarities.
8.      Derive an expression for specific speed for pump.
9.      Derive an expression for specific speed for turbine.
10.  Explain with neat sketch the working principle of  Centrifugal pump
11.  Explain with neat sketch the working principle of Reciprocating pump.
12.  Explain with neat sketch the working principle of  Pelton wheel turbine
13.  Explain with neat sketch the working principle of  Kaplan turbine
14.  Explain with neat sketch the working principle of  Reaction turbine
15.  Explain with neat sketch the working principle of rotary pump( Gear / Vane pump)
16.  Derive the efficiencies in centrifugal pump
17.  Derive the amount of work saved by air vessel in reciprocating pump.

ME 2202 ENGINEERING THERMO DYNAMICS ANNA UNIVERSITY QUESTION BANK FOR MECHANICAL ENGINEERING

ENGINEERING THERMO DYNAMICS (ME 2202) QUESTION BANK WITH ANSWERS ENGINEERING THERMO DYNAMICS (ME 2202) QUESTION BANK WITH ANSWERS
QUESTION BANK
ANNA UNIVERSITY QUESTION BANK FOR MECHANICAL ENGINEERING



QUESTION BANK

1.      ENGINEERING THERMO DYNAMICS (ME 2202)
1.      What do you understand by pure substance?
A pure substance is defined as one that is homogeneous and invariable in
chemical composition throughout its mass.
2.      Define thermodynamic system.
A thermodynamic system is defined as a quantity of matter or a region in space,
on which the analysis of the problem is concentrated.
3.      Name the different types of system.
Closed system (only energy transfer and no mass transfer)
Open system (Both energy and mass transfer)
Isolated system (No mass and energy transfer)
4.      Define thermodynamic equilibrium.
If a system is in Mechanical, Thermal and Chemical Equilibrium then the system
is in thermodynamically equilibrium. (or)
If the system is isolated from its surrounding there will be no change in the
macroscopic property, then the system is said to exist in a state of thermodynamic equilibrium.
5.      What do you mean by quasi-static process?
Equilibrium state
Quasi-static process
Infinite slowness is the characteristic feature of a quasi-static process. A quasistatic process is that a succession of equilibrium states. A quasi-static process is also called as reversible process.
6.      Define Path function.
The work done by a process does not depend upon the end of the process. It
depends on the path of the system follows from state 1 to state 2. Hence work is
called a path function.
7.      Define point function.
Thermodynamic properties are point functions. The change in a thermodynamic
property of a system is a change of state is independent of the path and depends
only on the initial and final states of the system.
8.      Name and explain the two types of properties.
The two types of properties are intensive property and extensive property.
Intensive Property: It is independent of the mass of the system. Example:
pressure, temperature, specific volume, specific energy, density.
Extensive Property: It is dependent on the mass of the system. Example:
Volume, energy. If the mass is increased the values of the extensive properties
also increase.
9.      Explain homogeneous and heterogeneous system.
The system consist of single phase is called homogeneous system and the system consist of more than one phase is called heterogeneous system.
10. What is a steady flow process?
Steady flow means that the rates of flow of mass and energy across the control
surface are constant.
11. Prove that for an isolated system, there is no change in internal energy.
In isolated system there is no interaction between the system and the
surroundings. There is no mass transfer and energy transfer. According to first
law of thermodynamics as dQ = dU + dW; dU = dQ – dW; dQ = 0, dW = 0,
There fore dU = 0 by integrating the above equation U = constant, therefore the
internal energy is constant for isolated system.
12. Indicate the practical application of steady flow energy equation.
1.      Turbine, 2. Nozzle, 3. Condenser, 4. Compressor.
13. Define system.
It is defined as the quantity of the matter or a region in space upon which we
focus attention to study its property.
14. Define cycle.
It is defined as a series of state changes such that the final state is identical with
the initial state.
15. Show that work is a path function and not a property.
16. Explain Mechanical equilibrium.
If the forces are balanced between the system and surroundings are called
Mechanical equilibrium
17. Explain Chemical equilibrium.
If there is no chemical reaction or transfer of matter form one part of the system to another is called Chemical equilibrium
18. Explain Thermal equilibrium.
If the temperature difference between the system and surroundings is zero then it
is in Thermal equilibrium.
19. Define Zeroth law of Thermodynamics.
When two systems are separately in thermal equilibrium with a third system then
they themselves are in thermal equilibrium with each other.
20. What are the limitations of first law of thermodynamics?
a.      According to first law of thermodynamics heat and work are mutually convertible during any cycle of a closed system.
b.      But this law does notspecify the possible conditions under which the heat is converted intowork.
c.      According to the first law of thermodynamics we can’t prove that  it is impossible to transfer heat from lower temperature to higher temperature.
d.      It does not give any information regarding change of state or whether theprocess is possible or not.
e.      The I law does not specify the direction of heat and work.
21. What is perpetual motion machine of first kind?
It is defined as a machine, which produces work energy without consuming an
equivalent of energy from other source. It is impossible to obtain in actual
practice, because no machine can produce energy of its own without consuming
any other form of energy.
22. Define Clausius statement.
It is impossible for a self-acting machine working in a cyclic process, to transfer
heat from a body at lower temperature to a body at a higher temperature without
the aid of an external agency.
23. What is Perpetual motion machine of the second kind?
A heat engine, which converts whole of the heat energy into mechanical work is
known as Perpetual motion machine of the second kind.
24. Define Kelvin Planck Statement.
It is impossible to construct a heat engine to produce network in a complete cycle
if it exchanges heat from a single reservoir at single fixed temperature.
25. Define Heat pump.
A heat pump is a device, which is working in a cycle and transfers heat from
lower temperature to higher temperature.
26. Define Heat engine.
Heat engine is a machine, which is used to convert the heat energy into mechanical work in a cyclic process.
27. What are the assumptions made on heat engine?
a.      The source and sink are maintained at constant temperature.
b.      The source and sink has infinite heat capacity.
28. State Carnot theorem.
It states that no heat engine operating in a cycle between two constant temperature heat reservoir can be more efficient than a reversible engine operating betweenthe same reservoir.
29. What is meant by reversible process?
A reversible process is one, which is performed in such a way that at the
conclusion of process, both system and surroundings may be restored to their
initial state, without producing any changes in rest of the universe.
30. What is meant by irreversible process?
The mixing of two substances and combustion also leads to irreversibility. All
spontaneous process is irreversible.
31. Explain entropy?
It is an important thermodynamic property of the substance. It is the measure of
molecular disorder. It is denoted by S. The measurement of change in entropy
for reversible process is obtained by the quantity of heat received or rejected to
absolute temperature.
32. What is absolute entropy?
The entropy measured for all perfect crystalline solids at absolute zero
temperature is known as absolute entropy.
33. Define availability.
The maximum useful work obtained during a process in which the final condition
of the system is the same as that of the surrounding is called availability of the
system.
34. Define available energy and unavailable energy.
Available energy is the maximum thermal useful work under ideal condition. The
remaining part, which cannot be converted into work, is known as unavailable
energy.
35. Explain the term source and sink.
Source is a thermal reservoir, which supplies heat to the system and sink is a
thermal reservoir, which takes the heat from the system.
36. What do you understand by the entropy principle?
The entropy of an isolated system can never decrease. It always increases and
remains constant only when the process is reversible. This is known as principle
of increase in entropy or entropy principle.
37. What are the important characteristics of entropy?
a.      If the heat is supplied to the system then the entropy will increase.
b.      If the heat is rejected to the system then the entropy will decrease.
c.      The entropy is constant for all adiabatic frictionless process.
d.      The entropy increases if temperature of heat is lowered without work being done as in throttling process.
e.      If the entropy is maximum, then there is a minimum availability for conversion in to work.
f.        If the entropy is minimum then there is a maximum availability forconversion into work.
38. What is reversed carnot heat engine? What are the limitations of carnot cycle?
   No friction is considered for moving parts of the engine.
        There should not be any heat loss.
39. Why Rankine cycle is modified?
The work obtained at the end of the expansion is very less. The work is too
inadequate to overcome the friction. Therefore the adiabatic expansion is
terminated at the point before the end of the expansion in the turbine and pressure decreases suddenly, while the volume remains constant.
40. Name the various vapour power cycle.
a.      Carnot cycle and
b.       Rankine cycle.
41. Define efficiency ratio.
The ratio of actual cycle efficiency to that of the ideal cycle efficiency is termed as efficiency ratio.
42. Define overall efficiency.
It is the ratio of the mechanical work to the energy supplied in the fuel. It is also
defined as the product of combustion efficiency and the cycle efficiency.
43. Define specific steam consumption of an ideal Rankine cycle.
It is defined as the mass flow of steam required per unit power output.
44. Name the different components in steam power plant working on Rankine cycle. Boiler, Turbine, Cooling Tower or Condenser and Pump.
45. What are the effects of condenser pressure on the Rankine Cycle?
By lowering the condenser pressure, we can increase the cycle efficiency. The main disadvantage is lowering the back pressure in rease the wetness of steam. Isentropic compression of a very wet vapour is very difficult.
46. Mention the improvements made to increase the ideal efficiency of Rankine cycle.
1.      Lowering the condenser pressure.
2.      Superheated steam is supplied to the turbine.
3.      Increasing the boiler pressure to certain limit.
4.      Implementing reheat and regeneration in the cycle.
47. Why reheat cycle is not used for low boiler pressure?
At the low reheat pressure the heat cycle efficiency may be less than the Rankine cycle efficiency. Since the average temperature during heating will then be low.
48. What are the disadvantages of reheating?
Reheating increases the condenser capacity due to increased dryness fraction,
increases the cost of the plant due to the reheats and its very long connections.
49. What are the advantages of reheat cycle?
1.      It increases the turbine work.
2.      It increases the heat supply.
3.      It increases the efficiency of the plant.
4.      It reduces the wear on the blade because of low moisture content in LP state of the turbine.
50. Define latent heat of evaporation or Enthalpy of evaporation.
The amount of heat added during heating of water up to dry steam from boiling point is known as Latent heat of evaporation or enthalpy of evaporation.
51. Explain the term super heated steam and super heating.
The dry steam is further heated its temperature raises, this process is called as superheating and the steam obtained is known as superheated steam.
52. Explain heat of super heat or super heat enthalpy.
The heat added to dry steam at 100oC to convert it into super heated steam at the temperature Tsup is called as heat of superheat or super heat enthalpy.
53. Explain the term critical point, critical temperature and critical pressure.
In the T-S diagram the region left of the waterline, the water exists as liquid. In
right of the dry steam line, the water exists as a super heated steam. In between
water and dry steam line the water exists as a wet steam. At a particular point, the water is directly converted into dry steam without formation of wet steam. The point is called critical point. The critical temperature is the temperature above which a substance cannot exist as a liquid, the critical temperature of water is 374.15oC. The corresponding pressure is called critical pressure.
54. Define dryness fraction (or) What is the quality of steam?
It is defined as the ratio of mass of the dry steam to the mass of the total steam.
55. Define enthalpy of steam.
It is the sum of heat added to water from freezing point to saturation temperature
and the heat absorbed during evaporation.
56. How do you determine the state of steam?
If V>vg then super heated steam, V= vg then dry steam and V< vg then wet steam.
57. Define triple point.
The triple point is merely the point of intersection of sublimation and vapourisation curves.
58. Define heat of vapourisation.
The amount of heat required to convert the liquid water completely into vapour
under this condition is called the heat of vapourisation.
59. Explain the terms, Degree of super heat, degree of sub-cooling.
The difference between the temperature of the superheated vapour and the
saturation temperature at the same pressure. The temperature between the saturation temperature and the temperature in the sub cooled region of liquid.
60. What is the purpose of reheating?
The purpose of reheating is to increase the dryness fraction of the steam passing
out of the later stages of the turbine.
61. Define Ideal gas.
It is defined as a gas having no forces of intermolecular attraction. These gases
will follow the gas laws at all ranges of pressures and temperatures.
62. Define Real gas.
It is defined, as a gas having the forces of attraction between molecules tends to
be very small at reduced pressures and elevated temperatures.
63. What is equation of state?
The relation between the independent properties such as pressure, specific volume and temperature for a pure substance is known as the equation of state.
64. State Boyle’s law.
It states that volume of a given mass of a perfect gas varies inversely as the
absolute pressure when temperature is constant.
65. State Charle’s law.
It states that if any gas is heated at constant pressure, its volume changes directly as its absolute temperature.
66. Explain the construction and give the use of generalized compressibility chart.
The general compressibility chart is plotted with Z versus Pr for various values of
Tr. This is constructed by plotting the known data of one of mole gases and can
be used for any gas. This chart gives best results for the regions well removed
from the critical state for all gases.
67. What do you mean by reduced properties?
The ratios of pressure, temperature and specific volume of a real gas to the
corresponding critical values are called the reduced properties.
68. Explain law of corresponding states.
If any two gases have equal values of reduced pressure and reduced temperature, then they have same values of reduced volume.
69. Explain Dalton’s law of partial pressure.
The pressure of a mixture of gases is equal to the sum of the partial pressures of
the constituents. The partial pressure of each constituent is that pressure which
the gas would expect if it occupied alone that volume occupied by the mixtures at
the same temperatures. m = mA+mB+mC+……. = _mi
mi = mass of the constituent.
P=PA+PB+PC+……. = _Pi, Pi – the partial pressure of a constituent.
70. State Avogardo’s Law.
The number of moles of any gas is proportional to the volume of gas at a given pressure and temperature.
71. What is Joule-Thomson coefficient?
The temperature behaviors of a fluid during a throttling (h=constant) process is described by the Joule-Thomson coefficient defined as
µ =[dT/dP]n
72. What is compressibility factor?
The gas equation for an ideal gas is given by (PV/RT) = 1, for real gas (PV/RT) is
not equal to 1 (PV/RT) = Z for real gas is called the compressibility factor.
73. What is partial pressure?
The partial pressure of each constituent is that pressure which the gas would exert if it occupied alone that volume occupied by the mixtures at the same
temperature.
74. Define Dalton’s law of partial pressure.
The total pressure exerted in a closed vessel containing a number of gases is equl to the sum of the pressures of each gas and the volume of each gas equal to the volume of the vessel.
75. How does the Vander Waal’s equation differ from the ideal gas equation of state?
     The ideal gas equation pV=mRT has two important assumptions,
1.      There is little or no attraction between the molecules of the gas.
2.      That the volume occupied by the molecules themselves is negligibly small compared to the volume of the gas. This equation holds good for low pressure and high temperature ranges as the intermolecular attraction and the volume of the molecules are not of much significance.
As the pressure increases, the inter molecular forces of attraction and repulsion
increases and the volume of the molecules are not negligible. The real gas deviate considerably from the ideal gas equation
[p+(a/V2)](V-b) = RT
76. What is humidification and dehumidification?
The addition of water vapour into air is humidification and the removal of water
 vapour from air is dehumidification.
77. Differentiate absolute humidity and relative humidity.
Absolute humidity is the mass of water vapour present in one kg of dry air.
Relative humidity is the ratio of the actual mass of water vapour present in one kg of dry air at the given temperature to the maximum mass of water vapour it can with hold at the same temperature. Absolute humidity is expressed in terms of kg/kg of dry air. Relative humidity is expressed in terms of percentage.
78. What is effective temperature?
The effective temperature is a measure of feeling warmth or cold to the human
 body in response to the air temperature, moisture content and air motion. If the
air at different DBT and RH condition carries the same amount of heat as the heat carried by the air at temperature T and 100% RH, then the temperature T is
known as effective temperature.
79. Represent the following psychrometric process using skeleton psychrometric
chart? a) Cooling and dehumidification, b) Evaporative cooling.
80. Define Relative humidity.
It is defined as the ratio of partial pressure of water vapour (pw) in a mixture to the
saturation pressure (ps) of pure water at the same temperature of mixture.
81. Define specific humidity.
It is defined as the ratio of the mass of water vapour (ms) in a given volume to the
mass of dry air in a given volume (ma).
82. Define degree of saturation.
It is the ratio of the actual specific humidity and the saturated specific humidity at
the same temperature of the mixture.
83. What is dew point temperature?
The temperature at which the vapour starts condensing is called dew point
temperature. It is also equal to the saturation temperature at the partial pressure of water vapour in the mixture. The dew point temperature is an indication of
specific humidity.
84. What is meant by dry bulb temperature (DBT)?
The temperature recorded by the thermometer with a dry bulb. The dry bulb
thermometer cannot affected by the moisture present in the air. It is the measure
of sensible heat of the air.
85. What is meant by wet bulb temperature (WBT)?
It is the temperature recorded by a thermometer whose bulb is covered with
cotton wick (wet) saturated with water. The wet bulb temperature may be the
measure of enthalpy of air. WBT is the lowest temperature recorded by
moistened bulb.
86. Define dew point depression.
It is the difference between dry bulb temperature and dew point temperature of air vapour mixture.
87. What is meant by adiabatic saturation temperature (or) thermodynamic wet bulb temperature?
It is the temperature at which the outlet air can be brought into saturation state by
passing through the water in the long insulated duct (adiabatic) by the evaporation of water due to latent heat of vapourisation.
88. What is psychrometer?
Psychrometer is an instrument which measures both dry bulb temperature and wet bulb temperature.
89. What is psychrometric chart?
It is the graphical plot with specific humidity and partial pressure of water vapour
in y axis and dry bulb temperature along x axis. The specific volume of mixture,
wet bulb temperature, relative humidity and enthalpy are the properties appeared
in the psychrometric chart.
90. Define sensible heat and latent heat.
Sensible heat is the heat that changes the temperature of the substance when
added to it or when abstracted from it. Latent heat is the heat that does not affect
the temperature but change of state occurred by adding the heat or by abstracting the heat.
91. What are the important psychrometric process?
1.Sensible heating and sensible cooling, 2. Cooling and dehumidification,                3.Heating and humidification, 4. Mixing of air streams, 5. Chemical
dehumidification, 6. Adiabatic evaporative cooling.
92. What is meant by adiabatic mixing?
The process of mixing two or more stream of air without any heat transfer to the surrounding is known as adiabatic mixing. It is happened in air conditioning system.
93. What are the assumptions made in Van Der waal’s equation of state?
There is no inter molecular forces between particles. The volume of molecules is negligible in comparison with the gas.
94. Define coefficient of volume expansion.
     The coefficient of volume expansion is defined as the change in volume with the change in temperature per unit volume keeping the pressure constant. It is denoted by b.
95. State Helmholtz function.
Helmholtz function is the property of a system and is given by subtracting the product of absolute temperature (T) and entropy (S) from the internal energy (U).
            Helmholtz function = U – TS
96. What are thermodynamic properties?
 Thermodynamic properties are pressure (p), temperature (T), volume (V), internal energy (U), enthalpy(H), entropy (S), Helmholtz function (a) and Gibbs function
97. Define throttling process.
When a fluid expands through a minute orifice or slightly opened valve, the
process is called as throttling process. During this process, pressure and velocity
are reduced.
98. Define Molecular mass.
Molecular mass is defined as the ratio between total mass of the mixture to the total number of moles available in the mixture.
99. Define isothermal compressibility.
Isothermal compressibility is defined as the change in volume with change in pressure per unit volume keeping the temperature constant.
100.                        Define psychrometry.
The science which deals with the study of behaviour of moist air (mixture of dry
            air and water vapour) is known as psychrometry.



   1. A system receives 42 kJ of heat while expanding with volume change of 0.123 m3 against an atmosphere of

         12 N/cm2. A mass of 80 kg in the surroundings is also lifted through a distance of 6 metres.
(i)                 Find the change in energy of the system.
(ii)               The system is returned to its initial volume by an adiabatic process which requires 100 kJ of work. Find  the change in energy of system.
(iii)             Determine the total change in energy of the system.
[Ans. (i) 22.54 kJ, (ii) 100 kJ, (iii) 122.54 kJ]

   2. A tank contains 2.26 m3 of air at a pressure of 24.12 bar. If air is cooled until its pressure and temperature becomes 13.78 bar and 21.1°C respectively. Determine the decrease of internal energy.

[– 5857.36 kJ]

   3. Determine work done by fluid in the thermodynamic cycle comprising of following processes :

(a) Unit mass of fluid at 20 atm and 0.04 m3 is expanded by the law PV1.5 = constant, till volume gets doubled.
(b) Fluid is cooled isobarically to its original volume.
(c) Heat is added to fluid till its pressure reaches to its original pressure, isochorically.
 [18.8 kJ]

   4. Air at 8 bar, 100°C flows in a duct of 15 cm diameter at rate of 150 kg/min. It is then throttled by a valve upto 4 bar pressure. Determine the velocity of air after throttling and also show that enthalpy remains constant before and after throttling.

[37.8 m/s]

   5. Determine the power required by a compressor designed to compress atmospheric air (at 1 bar, 20°C)

 to 10 bar pressure. Air enters compressor through inlet area of 90cm2 with velocity of 50 m/s and leaves with velocity of 120 m/s from exit area of 5 cm2. Consider heat losses to environment to be 10% of power input to compressor.                                                                                                                                                                                                                  [50.4 kW]

   6. A frictionless piston is free to move in a closed cylinder. Initially there is 0.035 m3 of oxygen at 4.5 bar, 60°C on one side of the piston and 0.07 m3 of methane at 4.5 bar and – 12°C on the other side. The cylinder walls and piston may be regarded as perfect thermal insulators but the oxygen may be heated electrically. Heating takes place so that the volume of oxygen doubles. Find :

(i)                 Final state condition ; (ii) Work done by the piston ;
(ii)               Heat transferred to oxygen.
Treat both gases as perfect and take :
For oxygen cp = 0.88 kJ/kg K, R = 0.24 kJ/kg K
      For methane cp = 1.92 kJ/kg K, R = 0.496 kJ/kg K.

   7. The specific heat at constant pressure of one kg fluid undergoing a non-flow constant pressure process is

            given by






where T is in °C.
           The pressure during the process is maintained at 2 bar and volume changes from 1 m3 to 1.8 m3 
           and temperature changes from 50°C to 450°C.
Determine :
(i) Heat added (ii) Work done
(iii) Change in internal energy (iv) Change in enthalpy.
8.      The resistance of the winding in a certain motor is found to be 75 ohms at room (25oC). When operating at full load under steady state conditions, the motor is switched off and the resistance of the winding s is immediately measured again, and found to be 90 ohms. The windings are made of copper whose resistance at temperature toC id given by Rt = Ro [1+0.00393t] where R0 is the resistance at 00C. Find the temperature of the coil during full load

9.      A certain working fluid undergoes a process in such a way that pressure and volume are related as , Where p is in kPa and V is in m3 . During the process the volume changes from 0.15 m3 to 0.1 m3. Determine the work done in the process.                                                                                     

10.  A gas occupies 0.3m3 at 2 bar. It undergoes a cycle  consisting of the following processes a)1-2 constant pressure process with work interaction of 15kJ  b)2-3 constant temperature process and E3=E2  c) 3-1 constant volume and change in internal energy E1-E3 is-40kJ. Determine network and net heat transfer for the cycle.                                                                                                                      
11.  A piston-cylinder assembly contains 1kg or nitrogen at 100 kPa.  The initial volume is 0.5 m3.  Heat is transferred to the substance in an amount necessary to cause a slow expansion at constant temperature.  This process is terminated when the final volume is twice the initial volume. Estimate the amount of heat transferred.[Molecular wt. 28 & Cv=0.773 kJ/kgK]                   

12.  0.115m3  of gas has a pressure of 138 kN /m2. It is compressed to 680 kN /m2according to the law PV1.4 =C, Determine the volume of the gas, work done and heat transferred.

13.  The gas is compressed from initial state of 0.35 m3 and 105 kPa to a final state of 0.14 m3 and to the same pressure .Determine the change in internal energy of the gas which transfers 38 kJ of heat. 

14.  A piston and cylinder device contains 1 kg of air, Initially, v = 0.8 m3/kg and
T = 298 K.  The air is compressed in a slow frictionless process to a specific volume of 0.2 m3/kg and a temperature of 580 K according to the equation pV1.3 = 0.75 ( p in bar, v in m3/kg).  If Cv of air is 0.78 kJ/kg determine :
work and
 heat transfer (both in kJ)
15.  A piston-cylinder assembly contains 1kg or nitrogen at 100 kPa.  The initial volume is 0.5 m3.  Heat is transferred to the substance in an amount necessary to cause a slow expansion at constant temperature.  This process is terminated when the final volume is twice the initial volume. Estimate the amount of heat transferred.[Molecular wt. 28 & Cv=0.773 kJ/kgK](16)
16.  A closed system undergoes a cycle consisting of three process 1-2, 2-3 and 3-1.  Given that Q12 = 30 kJ, Q23 = 10 kJ, 1w2 = 5 kJ, 3w2 = 5 kJ and DE31 = 15 kJ, determine Q31, w23, DE12 and DE23.
                     
17.  The following cycle involves 3 kg of air :  Polytropic compression from 1 to 2 where P1 = 150 kPa, T1 = 360 K, P2 = 750 kPa and n = 1.1 ; constant-pressure cooling from 2 to 3; and constant - temperature heating from 3 to 1.  Draw the pV diagram and find temperatures, pressures and volumes at each state and determine the net work and heat.

  18. A reversible engine is operating between 1000 K and 300 K. Find the efficiency of the engine. Also find the power developed, in kW if the amount of heat received from high temperature reservoir is 500 kJ per min.


  19. A refrigerator operating on reversible cycle is pumping heat from -5oC to the atmosphere at 40oC. If it has to pump 24000 kJ/hr, find the power required to run the refrigerator.



  20. Calculate the power developed and diameter of the inlet pipe, if air enters at 5 kg/s, 50m/s with an enthalpy of 0.9 MJ/kg and leaves at 150 m/s with an enthalpy of 0.4 MJ/kg. The heat loss to the surroundings is 0.025MJ/kg. Assume 100kPa and 300 K at the inlet


  21. In an isentropic flow through nozzle, air flow at the rate of 600 kg/hr. At inlet to

      the nozzle, pressure is 2MPa and temperature is 127oC. The exit pressure is 0.5
      MPa. Initial air velocity is 300 m/s determine exit velocity of air, inlet and exit
      area of nozzle.

  22. Two heat engines operating on carnot cycle are arranged in series. The engine A

       receives heat at 1000 K and rejects heat at a constant temperature T2. The engine
       B receives heat rejected by A, and in turn rejects heat to a reservoir at 300 K.
       Calculate the T2 when a) the efficiency of the two engines are equal b) the work
       output of the two engines are equal.

  23. A carnot engine receives 90kJ from a reservoir at 900 K. It rejects heat to he

      environment at 300 K. One-fifth of its work output is used to drive a carnot
      refrigerator. The refrigerator rejects 60 kJ to the environment at 300 K. Find work
      output and efficiency of the engine, the temperature of the sink for the refrigerator in 
      degree celsius.

24.  Three reversible engines of Carnot type are operating in series between the limiting temperatures of 1100 K and 300 K. Determine the intermediate temperatures if the work output from engines is in proportion of 3 : 2 : 1.   
                                                                 
25.  In a compressor the air enters at 27°C and 1 atm and leaves at 227°C and 1 MPa. Determine the work done per unit mass of air assuming velocities at entry and exit to be negligible. Also determine the additional work required, if velocities are 10 m/s and 50 m/s at inlet and exit respectively.                                                                                                                               
26.  In a gas turbine installation air is heated inside heat exchanger upto 750°C from ambient temperature of 27°C. Hot air then enters into gas turbine with the velocity of 50 m/s and leaves at 600°C. Air leaving turbine enters a nozzle at 60 m/s velocity and leaves nozzle at temperature of 500°C. For unit mass flow rate of air determine the following assuming adiabatic expansion in turbine and nozzle,
(i)                 heat transfer to air in heat exchanger
(ii)               power output from turbine
(iii)             velocity at exit of nozzle.
Take cp for air as 1.005 kJ/kg°K.                                                                                                               
27.  A refrigerator operates on reversed Carnot cycle. Determine the power required to drive refrigerator between temperatures of 42ºC and 4ºC if heat at the rate of 2 kJ/s is extracted from the low temperature region.  

28.  A piston and cylinder machine containing a fluid system has a stirring device as shown in Fig. 1.1 The piston is frictionless, and it is held down against the fluid due to atmospheric pressure of 101.3 kPa. The stirring device is turned 9500 revolutions with an average torque against the fluid of 1.25 Nm. Meanwhile the piston of 0.65 m diameter moves out 0.6 m. Find the net work transfer for the system.                                                                                                












Fig. 1.1
29.  At the inlet to a certain nozzle the enthalpy of fluid passing is 2800 kJ/kg, and the velocity is 50 m/s. At the discharge end the enthalpy is 2600 kJ/kg. The nozzle is horizontal and there is negligible heat loss from it.
a.       Find the velocity at exit of the nozzle.
b.      If the inlet area is 900 cm2 and the specific volume at inlet is 0.187 m3/kg, find the mass flow rate.
c.       If the specific volume at the nozzle exit is 0.498 m3/kg, find the exit area of nozzle.     [8]

30.  A fluid system, contained in a piston and cylinder machine, passes through a complete cycle of four processes. The sum of all heat transferred during a cycle is – 340 kJ. The system completes 200 cycles per min. Complete the following table showing the method for each item, and compute the net rate of work output in kW.                                                        [8]
Process           Q (kJ/min)                 W (kJ/min)                 ΔE (kJ/min)
   



1—2                  0                                4340                            —
2—3                42000                          0                                 —
3—4                –4200                          —                                – 73200
                        4—1                —                               —                                ___    

                                                                                  
31.  During flight, the air speed of a turbojet engine is 250 m/s. Ambient air temperature is – 14°C. Gas temperature at outlet of nozzle is 610°C. Corresponding enthalpy values for air and gas are respectively 250 and 900 kJ/kg. Fuel air ratio is 0.0180. Chemical energy of fuel is 45 MJ/kg. Owing to incomplete combustion 6% of chemical energy is not released in the reaction. Heat loss from the engine is 21 kJ/kg of air. Calculate the velocity of the exhaust jet.                           [8]
                                                                                                    
32.  The connections of a reversible engine to three sources at 500 K, 400 K and 300 K are shown in Fig. 1.3. It draws 1500 kJ/min of energy from the source at 500 K and develops 200 kJ/min of work.
a.       Determine the heat interactions with the other two sources of heat.
b.      Evaluate the entropy change due to each heat interaction with the engine.
c.       Total entropy change during the cycle.                                                                           [8]












33.  3 kg of water at 80°C is mixed with 4 kg of water at 15°C in an isolated system. Calculate the change of entropy due to mixing process.                                                                                    

34.  Two tanks A and B contain 1 kg of air at 1 bar, 50ºC and 3 bar, 50ºC when atmosphere is at 1 bar,15ºC. Identify the tank in which stored energy is more. Also find the availability of air in each tank.                            

                                                                                          
35.  A cold storage plant of 40 tonnes of refrigeration capacity runs with its performance just
            1/4 th of itsCarnot COP. Inside temperature is –15ºC and atmospheric temperature is 35ºC. Determine the powerrequired to run the plant. [Take : One ton of refrigeration as 3.52 kW]
                                                                                                                                                     

36.  A vessel of volume 0.2 m3 has 2 kg of water at 200 o C find p, h and x             
                             
37.  In a power station, the saturated steam is generated at 200ºC by transferring the heat from hot gases in a steam boiler. Find the increase in total entropy of the combined system of gas and water and increase in unavailable energy due to irreversible heat transfer. The gases are cooled from 1000°C to 500°C and all the heat from gases goes to water. Assume water enters the boiler at saturated condition and leaves as saturated steam 

                                                                                                                             
38.  One kg of air is compressed polytropically from 1 bar pressure and temperature of 300 K to a pressure of 6.8 bar and temperature of 370 K. Determine the irreversibility if the sink temperature is 293 K. Assume R = 0.287 kJ/kg K, cp = 1.004 kJ/kg K and cv = 0.716 kJ/kg K.

39.  water is heated from 40oC in a piston cylinder arrangement until it becomes s aturated
         vapour at a constant pressure of 50 bar. Find the heat to added per kg.                                            

40.  A steam power plant works between 40 bar and 0.05 bar. If the steam supplied is dry saturated and  the  cycle of operation  is Rankine, find : (i) Cycle efficiency (ii) Specific steam consumption.              

41.  In a regenerative cycle the inlet conditions are 40 bar and 400°C. Steam is bled at 10 bar in  Regenerative heating. The exit pressure is 0.8 bar. Neglecting pump work determine the efficiency of   the cycle.                                                                                                                          

42.  A steam power plant operates on ideal Rankine cycle using reheater and regenerative feed water heaters. It has one open feed heater. Steam is supplied at 150 bar and 600°C.The condenser pressure is 0.1 bar. Some steam is extracted from the turbine at 40 bar for closed feed water heater and remaining steam is reduced at 40 bar to 600°C. Extracted steam is completely condensed in this closed feed water heater and is pumped to 150 bar before mixing with the feed water heater. Steam for the open feed water heater is bled from L.P. turbine at 5 bar. Determine :
            (i) Fraction of steam extracted from the turbines at each bled heater, and
            (ii) Thermal efficiency of the system.
            Draw the line diagram of the components and represent the cycle on T-s diagram.                          



43.  The atmospheric conditions are 30ºC and specific humidity of 0.0215 kg/kg of air. Determine :
(i)                 Partial pressure of air
(ii)                Relative humidity
(iii)      Dew point temperature.
      Atmospheric pressure = 756 mm Hg.                                                                                                  

44.  1 kg of air at 24ºC and a relative humidity of 70% is to be mixed adiabatically in a steady state, steady flow device with 1 kg of air at 16ºC and a relative humidity of 10%. Assuming that the mixing is to be  carried out at a constant pressure of 1.0 atm, determine the temperature and relative humidity of  the  stream leaving the device.                                                                                                                   

45.  In a laboratory test, a psychrometer recorded 36ºC DBT and 30ºC WBT. Calculate :
(i)                 Vapour pressure
(ii)                Relative humidity
(iii)              Specific humidity
(iv)              Degree of saturation
(v)                 Dew point temperature
(vi)               Enthalpy of the mixture.                    

46.  An air-water vapour mixture enters an adiabatic saturator at 30ºC and leaves at 20ºC, which is the adiabatic  saturation temperature. The pressure remains constant at 1 bar. Determine the relative  humidity and the humidity ratio of the inlet mixture.                                                                        

                                              
47.  The following observation were made during a testing of moist air
                        Dry bulb temperature Tdb        =          29oC
                        Dew point temperature Tdb     =          15oC
                        Total pressure                          =          1 bar
            Determine the relative humidity and degree of saturation

48       In a combined heating and humidification process, moist air enters heating coil with the dry bulb temperature 20oC and 30% R.M. After the process the drug bulb temperature and the RH of Air were found to be 40oC and 55% RH. The air passes through the heating at the rate of 350 kg/min

49    In an air conditioning plant, fresh air is used to mix up with returned air from conditioned space. The fresh air drawn from atmosphere has the drug bulb temperature 32oC and we bulb temperature 25oC. The fresh air is drawn at the rate of 100m3/min. The returned air from conditioned space has the drug bulb temperature 23oC and relative humidity 50%. The volume flow rate of it 540 m3/min. Determine the (i) dry bulb and web bulb temperature (ii) specific humidity of mixture

50             Find the value of co-efficient of volume expansion β and isothermal compressibility K for a Van der Waals’ gas obeying