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    M.A.M. SCHOOL OF ENGINEERING ME2202

    Department of Mechanical Engineering ENGINEERING THERMODYNAMICS

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    M.A.M. SCHOOL OF ENGINEERING

    DEPARTMENT OF MECHANICAL ENGINEERING

    QUESTION BANK

    ME2202

    ENGINEERINGTHERMODYNAMICS

    SEMESTER: III

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    UNITI (PARTA)

    1. Define the term Thermodynamics?2. What is meant by Thermodynamics system? How do you classify it?3. What is meant by closed system? Give an example?4. Define open system? Give an example?5. Distinguish between open & closed system?6. Define isolated system?7. Define specific heat capacity at constant pressure?8. Define specific heat capacity at constant volume?9. What is meant by surroundings?10.What is boundary?11.What is Thermodynamic property?12.Distinguish between Heat & Temperature?13.Define A following system are in open/closed/isolated

    (a) Boiler (b) Mixture of ice and water in a metal container (c) Wind mill

    14.How do you classify the property?15.Define extensive and intensive property?16.Differentiate extensive and intensive property?17.

    What do you understand by equilibrium of a system?

    18.When a system is said to be in Thermodynamic Equilibrium?19.State first law of thermodynamics and give any two corollaries?20.What is meant by perpetual motion of machine first kind?21.Prove that for an isolated system, there is no change in internal energy?22.Determine the molecular volume of any perfect gas at 600 N/m2and 300C. Universal

    gas constant may be taken as 8314J/kg mole0K

    23.Define the term Process?24.Define the term Cycle?25.What is meant by open and closed cycle?26.What is meant by reversible and irreversible process?27.What is point and path function?28.What is Quasi-static process?

    29.Define the term enthalpy?30.Define the term Internal energy?31.What is meant by thermodynamics work?32.Sketch isothermal expansion on p-V Diagram and state the property remain constant?33.Prove the difference in specific heat capacities equal to Cp- Cv= R?34.Define Zeroth law of Thermodynamics?35.Differentiate Ideal and Real gas?36.What are the limitations of first law of Thermodynamics?

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    37.Define the term Enthalpy?38.Define hyperbolic process?39.Define free expansion process?40.Define Throttling process?41.

    What is NTP & STP?42.A liquid mass 18 kg is heated from 250C to 850C. How much heat transfer isrequired? Take Cp = 4.2kJ / kg K.

    43.A Closed system receives an input of heat is 450 kJ. Determine the work done by thesystem?

    UNITI (PARTB)

    1. Mass of 15 kg of air in a piston cylinder device is heated from 250C to 900C bypassing current through a resistance heater inside the cylinder. The pressure inside the

    cylinder is held constant at 300Kpaduring the process and the heat loss of 60KJ

    occurs. Determine the Electrical energy supplied in kW-hr and change in internal

    energy?

    2. Calculate the distance moved by a locomotive from consuming 2 tones of coal if 10%of the heat generated by coal is converted into coal gas then into mechanical work.

    The tractive effort required is 30tonne of dead mass of locomotive is 2500 tones.

    Assume 1kg of coal librates 35000 kJ of heat on burning.

    3. The following data refers to a closed system, which undergoes a thermodynamicscycle consisting of four processes.

    Process Heat transfer kJ/min Work transfer kJ/min

    a-b 50,000 -

    b-c -5,000 34,200

    c-d -16,000 -2,200

    d-a - -3,000

    Show that the data is consistent with the first law of thermodynamics and calculate

    (a)Net rate of work output in MW(b) Efficiency of the cycle

    4. A paddle wheel fixed to a shaft of an engine revolves in a closed hollow vesselcontaining water. This closed vessel is connected freely on the shaft and restraint to

    its turning moment is proved by mass attached to its side. Find the temperature rise

    for the following observations.

    Engine rpm = 650, Load applied = 60 kg at a leverage of 1.2m,

    Quantity of water = 200 kg

    Duration of test

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    5. During the summer season a room measuring 10 x 13 x 6 m3 is cooled electricallyfrom initial temperature 280C to 200C. The air pressure inside the room is same as that

    of surroundings and is equal to 72 cm of Hg. The pressure remains constant during the

    cooling process. The cooling capacity of furniture and wall is 35kJ/k. The specificheat of air 1.005kJ/kg0k. Calculate the amount of electrical energy needed for cooling

    the room. How much air comes through gaps and windows during cooling period?

    6. 25 Peoples attended the farewell party in small size room10 x 8m and has a 5mceiling. Each person gives up about 350 kJ of heat / hour. Assuming that the room is

    completely sealed off and insulated, calculate the air temperature rise occurring within

    10 minutes. Assume Cp, Cvand R and each person occupies a volume of 0.05m3

    7. Prepare the chart for non flow process and derive the formula for pV& T relations,work done, internal energy, heat transfer, enthalpy & entropy

    8. Mass of 15kg of air in a piston cylinder device is heated from 25 0C to 900C bypassing current through a resistance heater inside the cylinder. The pressure inside the

    cylinder is held constant at 300 kPa during the process and a heat loss of 60 kJ occurs.

    Determine the electrical energy supplied in kWhr and change in internal energy.

    9. In a vessel of 10 kg of O2is heated in a reversible non flow constant volume process,so that pressure of O2 is increased two times that of initial value. The initial

    temperature is 200C. Calculate the final temperature, change in internal energy,

    change in enthalpy, heat transfer & entropy. Take R = 0.259kJ/kg0k

    Cv= 0.625kJ/kg0k for Oxygen

    10.5 kg of air at 400C and 1 bar is heated in a reversible non flow constant pressureprocess until the volume is doubled. Find (a) change in volume (b) work done(c) Change in internal energy (d) Change in enthalpy

    11.0.25 kg of air at a pressure of 1 bar occupies the volume of 0.3m3. If this air expandsisothermally to a volume of 0.09m3. Find the initial air temperature and final

    temperature, external work done, heat observed by the air, change in internal energy.

    12.1.5 kg of certain gas at pressure of 8bar and 20 0C occupies a volume of 0.05m3 itexpands adiabatically to a pressure of 0.9 bar and volume 0.73 m3Determine the work

    done during the process, gas constant, ratio of specific heats, value of two specific

    heats, change in internal energy and change in enthalpy.

    13.A 1 kg of ideal gas of molecular weight 30 and specific heat ratio 1.4 is compressedaccording to law of PV1.25 = C from 1bar absolute and 270C to pressure of 16bar

    Absolute. Calculate the temperature at the end of compression, heat rejected, work

    done on the gas during the process, change in enthalpy

    14.Derive the steady flow energy equation with its application?15.A turbine operates under steady flow condition receives steam at the following state

    pressure = 1.2Mpa, Temperature =1880C, Enthalpy = 2785 kJ/kg,

    velocity = 33.3m/sec and elevation = 3m. The steam leaves the turbine at the following

    state: pressure = 20Kpa, Enthalpy = 2512 kJ/kg, velocity = 100m/sec and

    elevation = 0m. Heat is lost to the surrounding at the rate of 0.29kJ/sec. If the rate

    steam flow to the turbine is 0.42kg/sec what is the power output of the turbine in KW

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    16.air at temperature of 150C , passes through a heat exchanger at velocity of 30m/s ,where as its temperature is raised 8000C. it then enters a turbine with the same

    velocity of 30 m/s and expands until the temperature falls to 6500C. On leaving the

    turbine, the air is taken at velocity of 60m/s to nozzle were it expands until the

    temperature has fallen to 500

    0

    C. if the air flow rate is 2 kg/sCalculate: the rate of heat transfer to the air in the heat exchanger, the power output

    from the turbine assuming no heat loss the velocity at exit from the nozzle

    Assuming no heat loss. take the enthalpy of air as h = Cpt, where Cp is the specific

    heat equals to 1.005kJ/kg k and t the temperature.

    17.A mass of air is initially at 2600C and 700Kpa and occupies 0.028m3. The air isexpanded at constant pressure to 0.084m3. A polytropic process with n = 1.5 is then

    carried out, following by constant temperature process all process are reversible

    (a)Sketch the cycle pV& Ts planes.(b)Find the heat received and rejected in the cycle.(c)Find the efficiency of cycle.

    18.A gas of mass 1.5kg undergoes a Quasi-Static expansion which follows a relationshipp=a+bV, where aand bare constants. The initial and final pressures are 1000 &

    200Kpa and the corresponding volumes are 0.2 & 1.2m3. The specific internal energy

    of the gas is given by the relation u = 1.5pV-85 kJ/kg where p is Kpa and V is in m 3.

    Calculate the net heat transfer and the maximum internal energy of the gas attain

    during expansion.

    19.Air flows steadily at the rate of 0.5kg/sec through an air compressor, entering at7m/sec velocity, 100 kPa pressure and 0.95 m3/kg, volume leaving at 5m/sec, 700kPa

    and 0.19 m3

    /kg. The internal energy of the rate leaving is 90kJ/kg greater than that ofthe air entering. Cooling water in compressor jackets absorbs heat from the air at the

    rate of 58kW (a) Compute the rate of shaft work input to air in kW. (b) Find the ratio

    of the inlet pipe diameter to the outlet pipe diameter.

    20.Define internal energy and prove that its point functions? And establish relationshipbetween the specific heat at constant pressure and specific heat at constant volume?

    UNITII (PARTA)

    1.

    State the KelvinPlanck statement of second law of Thermodynamics?2. State the Clausius statement of second law of Thermodynamics?3. State Carnots theorem?4. What are the Corollaries of Carnot theorems?5. Define PMM of second kind?6. What are the difference between a Heat pump and Refrigerator?7. What is meant by Heat Engine?8. Define the term COP?9. Write the expression for COP of a heat pump and a refrigerator?10.Why the Carnot cycle cannot be realized in practice?11.Why the Carnot cycle efficiency will be maximum?

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    12.What are the processes involved in Carnot cycle?13.Sketch the pV & Ts diagram of Carnot cycle?14.Is the second law independent of first law? How?15.Define Entropy?16.

    Write the expression for efficiency of Carnot cycle?17.Define change of Entropy. How is entropy compared with heat transfer and absolutetemperature?

    18.Define the term source, sink and reservoir?19.Why the performance of refrigerator and heat pump are given in terms of COP and

    not in terms of efficiency?

    20.Comments on the statements The entropy of universe tends to be maximum21.What is meant by principles in increase in entropy?22.What do you meant by clausius inequality23.Write down the equation for Carnot COP of a heat pump which works between two

    heat reservoirs of temperature T1and T2temperature?

    24.Explain briefly clausius inequality?25.For compression process between same and states which work will be more reversible

    or irreversible?

    26.A heat pump pumps 10MJ/KW.hr to the high temperature reservoir. What is theCOP?

    27.Find the entropy of universe when 1000KJ of heat is transferred from 8000K to5000K?

    28.Give the expression to find change in entropy during constant pressure and polytropicprocess. Show on T-s diagram?

    29.Explain the term Reversibility?30.Can entropy of universe ever decrease? Why?31.What is essence of second law of thermodynamics?32.If the Carnot engine efficiency is 50%. Find the COP of refrigerator working between

    same temperatures?

    33.Define the term Absolute Entropy?34.What are the causes of Irreversibility?35.Write the Corollaries of Carnot theorem?36.What is thermodynamics temperature scale?37.List out the applications of entropy?38.Define the term Availability?39.What is available energy?40.What is unavailable energy?

    UNITII (PARTB)

    1. Derive the expression for thermal efficiency of a Carnot cycle with its p-V and TsDiagram?

    2. Explain the Clasius inequality with its p-V diagram?

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    3. Derive the expression for change in entropy for the following process (i)Isochoric(ii) Isobaric (iii) Isothermal (iv) Isentropic (v) Polytropic

    4. Explain the absolute entropy, absolute enthalpy and absolute internal energy?5. An inventor claims to have developed a refrigerating unit which maintains the

    refrigerated space at -6

    0

    C while operating in a room where temperature is 27

    0

    C andhas COP 8.5. Find out whether his claim is correct or not?

    6. A heat engine is used to drive a heat pump. The heat transfer from a heat engine andfrom the heat pump is used to heat the water?

    7. A Carnot engine takes heat from an infinite reservoir at 5500C and rejects it to a sink2750C. Half of the work delivered by the engine is used to run generator and the

    other half is used to run heat pump which takes heat at 2750C and rejects it at 4400C.

    Express the heat rejected at 4400C by the heat pump as % of heat supplied to the

    engine at 5500C. If the operation of the generator is 500W, Find the heat

    rejected/hour by the heat pump at 4400C?

    8. A Heat engine operates between a source at 6000C and a sink at 600C. Determine theleast rate of heat rejection/ kW net output of the engine?

    9. 0.2kg of air at 1.5bar and 270C is compressed to a pressure of 15bar according to thelaw of PV1.25=C. Determine work done on or by air, heat flow to or from the air,

    increase or decrease in entropy?

    10.A reversible heat engine operates between a source at 8000C and a sink 300C. Whatare least rate of heat rejection / kW net work output of the engine?

    11.1 kg of ice melts at constant atmospheric pressure and at 00C to form liquid water. Ifthe latent heat of fusion of ice is 333.3kJ/kg, Calculate the entropy change during

    process?12.Explain the corollaries of second law of thermodynamics with suitable example?13.Three identical bodies of A, B & C constant heat capacity are at temperature of 300,

    300 & 100K. a heat engine is operated between A and B and a heat pump working as

    refrigerator is operated between B and C. The heat pump is operated by the output of

    the engine. If the work or heat supplied from outside, find the highest temperature to

    which any one of body can be raised by the operation of the heat engine or

    refrigerator?

    14.Explain reversibility?15.Find the change in entropy of 1kg of ice which is heated from -50C to 00C. Cp ice =

    2.093 kJ/kg0K. The pressure during heating is maintained at 1 atm constant. Latent

    heat of fusion of ice=334.96 kJ/kg

    16.Give the expression to find change in entropy during constant pressure?17.A domestic food freezer maintains a temperature of -150C. The ambient air is 300C.

    If the leaks into freezer at a continuous rate of 1.75kg/sec, What is the least power

    necessary to pump the heat out continuously?

    18.Derive absolute entropy for closed cycle processes?19.5kg of air at 2bar and 300C is compressed to 24bar pressure according to the law of

    PV1.2=C. After compression air is cooled at constant volume to 300C. Determine the

    volume and temperature at the end of compression, Change in entropy during

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    compression, Change in entropy during constant volume of cooling Take

    Cp=1.005kJ/kg0K, Cv=0.715kJ/kg

    0K.

    20.Derive the availability analysis to open cycle processes?

    UNITIII (PARTA)

    1. Define latent heat of Ice?2. What is pure substance?3. What is saturation pressure and temperature?4. Define latent heat of evaporation?5. Find the saturation temperature & latent heat of evaporation of steam at 1Mpa?6. Define the terms Boiling point and Melting point7. What is meant by superheated steam?8. What are the uses of superheated steam?9. Define: Sensible heat of water?10.Differentiate Wet steam and Dry Steam?11.State phase rule of pure substances?12.Define: Super heat enthalpy?13.Define dryness fraction of steam?14.What is degree of under cooling & Degree of sub cooling?15.Define triple point and critical point for pure substance?16.When saturation pressure increases, what happen to saturation temperature and

    freezing point?17.Draw the change of phase of water in T-V diagram?18.Draw the h-s diagram for steam and show a throttling process on it?19.Draw the skeleton p-V diagram of water?20.Draw the p-V-T surface of water?21.Write the formula for calculating entropy change from saturated water to superheated

    water to superheat condition?

    22.Determine the condition of steam of 2bar whose entropy is 6.27kJ/kg?23.Determine specific enthalpy and entropy of 1200Csaturated steam?24.

    Find the mass of 0.1m

    3

    of wet steam at a temperature of 160

    0

    C and 0.94 dry?25.One kg of 10bar has an enthalpy of 2500kJ/kg. Find its quality?26.What is meant by steam power cycle?27.Define the term efficiency ratio?28.What is meant by isentropic efficiency?29.Define specific steam consumption of an ideal Rankines cycle?30.What is meant by work ratio?31.What is the importance of work ratio in vapour cycles?32.Name the different process of Rankines cycle T-s diagram?33.What are the effects of condenser pressure on the cycle?34. A vapour cycle inherently has two advantages over gas power cycle?

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    35.What are the limits of maximum and minimum temperature in a steam power cycle?36.Mention the improvements made to increase the ideal cycle efficiency of Rankines

    cycle?

    37.Sketch the diagram of Rankines cycle indicating the main components?38.

    What are the effects of condenser pressure in Rankines cycle?39.Why Carnot cycle cannot be realized in practice for vapour cycle?

    40.What are the disadvantages of Reheating?41.List the advantages of Reheating?

    UNITIII (PARTB)

    1. Explain the process of steam formation with help of T-H diagram?2. Calculate the state of a steam using steam table.

    (a)Steam has a pressure of 15bar and specific volume of 0.12m3/kg(b)Steam has a pressure of 10bar and temperature of 2000C.(c)Steam has a pressure of 30bar and Enthalpy 2700kJ/kg.

    3. Explain the Phase rule?4. Draw the p-V diagram of pure substance and explain its various regions of the

    diagram in details?

    5. In a steam power plant operating on an ideal reheat Rankines cycle, the steam entersthe high pressure turbine at 3Mpa and 4000C. After expansion to 0.6Mpa, the steam is

    reheated to 4000C and then expanded the low pressure turbine to the condenser

    pressure of 10kPa. Determine the thermal efficiency of the cycle and the quality of the

    steam at the outlet of low pressure turbine?

    6. Draw the p-T diagram of pure substance and explain its various regions of thediagram in details?

    7. Explain the p-v-T surfaces of water and CO2?8. Explain mollier diagram with neat sketch and give advantages?9. A reheat cycle operating between 30bar to 0.04bar has a superheat and reheats

    temperature of 4500C. The first expansion takes place till the steam is dry saturated

    and then reheat is given. Neglecting feed pump work determines the ideal cycle

    efficiency?10.With help of T-s diagram explain the variousprocess of ideal Rankines cycle and

    derive the efficiency in terms of enthalpy?

    11.Why the Rankines cycle used as a standard reference for the steam power cyclerather than Carnot cycle?

    12.How can be the Rankines cycle modified for reciprocating steam engine plants?why?

    13.What is the effect of Rankines cycle efficiency when the steam is supplied at the inletof the turbine is (a) Dry saturated (a) wet with dryness fraction x and (c)

    Superheated?

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    14.Explain process of reheating with help of T-s diagram in the Rankines cycle? Why itis used?

    15.A steam power plant uses steam at boiler pressure of 150bar and temperature 500 0C atcondenser pressure of 0.1bar.find the quality of steam at turbine exhaust, cycle

    efficiency and steam rate?16.Explain the ideal regenerative Rankines cycle with help of T-s & diagram? What arethe effects of regeneration on efficiency of the cycle?

    17.Why the ideal regenerative cycle is not practical and how to modify it for practicalpurpose?

    18.Draw the schematic and T-s diagram for regenerative Rankines cycle with two feedwater heater, and obtain the expression for mass of steam extracted for each heater?

    19.In a single regenerative cycle the steam enters the turbine at 30bar and 4000C and theexhaust pressure is 0.1bar. The condensate is heated in a direct contact type heater

    which operates at 5bar. Find the efficiency and the steam rate of the cycle and the

    increase in mean temperature of heat addition, efficiency and steam rate as compared

    to the rankines cycle. Neglect the pump work?

    20.A steam boiler generates steam at 30bar; 3000C t the rate of 2kg/sec. the steam isexpanded isentropically in a turbine to a condenser pressure of 0.05bar, condensed at

    constant pressure and pumped back to boiler.

    (a)Draw the schematic arrangement of the above plant T-s diagram of Rankinescycle.

    (b)Find heat supplied in the boiler/hr.(c)Determine the quality of steam after expansion(d)What is power generated by the turbine(e)Estimate the Rankines efficiency considering pump work?

    UNITIV (PARTA)

    1) Determine the molecular volume of any perfect gas at 600N/m2 and 300C.Universal gas constant may be taken as 8314J/kg mole K?

    2) State Boyles law?3) State Joules law?4) State Renaults law?5) State Avogadros law?6) State Daltons law of partial pressure?7) How does the Vander waals equation differ from the ideal gas equation of state?8) What is meant by virtual expansion9) Distinguish between ideal and real gas?10)What is Maxwell relation?11)Define joule-Thomson co-efficient?12)Define co-efficient of volume expansion and isothermal compressibility?13)What is compressibility factor?

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    14)Draw the generalized compressibility chart?15)What does compressibility chart signify? And what is its value for an ideal gas at

    a critical point?

    16)Why joule-Thomson co-efficient is it Zero for an ideal gas?17)

    What is clapeyron Equation?18)State Tds equation?

    19)State the assumption made in kinetic energy theory of gases?20)State the Helmholtz function?21)State Gibbs function?22)What is mass fraction?23)What is Molar fraction?24)What is partial pressure and volume?25)What is pure substance?26)State Amagats law of partial pressure?27)What are the properties of gas mixtures?28)List the assumption are made for mixing of ideal gas?29)What is real gas?30)List properties of real gas?31)Air contains 21% of O2 and 79% of nitrogen by volume. Determine molecular

    weight of air, R and density at S.T.P?

    32)Differentiate STP & NTP?33)List properties of ideal gas?34)What is specific heat of an ideal gas?35)Write the enthalpy value of an ideal gas?36)What is equation state of ideal gas?37)What is intermolecular force?38)What is Shape factor?39)Write the Vendar Waals equation?40)What is Beattie-bridgeman equation of state?41)What is Benedict-Webb-Rubin equation of state?42)What is Virial equation of state?

    UNITIV (PARTB)

    1. State anyone equation of state for real gas and show how the deviation from ideal gasbehavior is accounted for?

    2. Prove the difference in specific heat capacities equal to Cp-Cv=R and Cp-Cv=TV2/kT3. Deduce the Maxwell relations from thermodynamic property relations?4. Using Maxwell relations Cp-Cv=TV2/kT where is the volume of expansivity and

    kT is the isothermal compressibility?

    5. Explain the construction and give the use of generalized compressibility chart?

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    6. Explain the flow process of a real gas through a throttle valve. Derive the expressionfor joule Thomson coefficient and deduce its value for an ideal gas?

    7. Methane at 1.013bar and 300C enters an insulated mixing chamber at rate of 5kg/sec.It is mixed with air at 1bar in an air/methane mass ratio of 18. The flow is stead and

    kinetic energy changes are negligible. Ambient pressure and temperature are 1.013barand 300C, determine (a) the temperature of the mixing /kg of methane. Take Cv and

    Cp of methane as 1.7354kJ/kg/k and 2.2537 kJ/kg/k respectively.

    8. Find the increase in entropy when 7.5kg of O2 at 700C are mixed with 8kg of nitrogenat the same temperature. The initial pressure of each constituents is 103kPa and is the

    same as that of mixture?

    9. Explain the Daltons law of partial pressure?10.A mixture of perfect gases at 250C contains 65% of N2, 20% O2and 25% CH4by

    volume. If the partial pressure of CH4is 65kPa, determine (a) The partial of N2and O2

    (b) Mass proportion of mixture (c) gas constant for the mixture and (d) Volume/mole

    of mixture.

    11.Compute the specific volume of steam at 1bar and 5500K using Vander waalsequation. Take critical temperature of steam is 647.30K and critical pressure is

    220.9bar.

    12.Explain the Clapeyron equation of partial pressure?13.Prove that Cp of ideal gas is a function of temperature only?14.A mixture of 2kg O2 and 2kg of Argon is in insulated piston cylinder arrangement at

    100kPa, 3000K. The piston now compresses the mixture to half its initial volume.

    Molecular weight of O2is 32 and for argon are 40. ratio of specific heats for O2is

    1.39 and for argon is 1.667.

    15.A mixture of Ideal gases consists of 3kg pf N2 and 5kg of CO2 at a pressure of300kPa and a temperature of 200C. Find (a) The mole fraction of each constituents

    (b) the equivalent Molecular weight of mixture (c) The equivalent gas constant of the

    mixture (d) The partial pressures and the partial volumes?

    16.0.45kg of CO and 1kg of air is contained in a vessel of volume 0.4m3at 150C. Air has23.3% of O2and 76.7% of N2by mass. Calculate the partial pressure of each

    constituents and total pressure in the vessel. Molar volume of CO, CO2and N2are 28,

    32 and 28kg/kmol.

    17.Obtain the expression for ds in terms of dT and dp?18.The equation of state in the range of pressure and temperature by v=RT/pC/T:

    where C is constant. Derive the expression for the change of enthalpy and entropy for

    this substance during an isothermal process?

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    19.Using Clausius Cleperyons equation, Estimate the enthalpy of vaporization at 2200Csaturation temperature. Take the following data Ts= 2200C; vg= 0.08603m

    3/kg;

    vf =0.00119m3/kg.

    20.Explain the Joules Thomson Co-efficient detailly?

    UNITV (PARTA)

    1. What is the difference between air conditioning and refrigeration?

    2. Define psychrometry?

    3. Name some psychrometric processes and represent them on the psychrometric chart?

    4. Define dry bulb temperature (DBT)?

    5. Define wet bulb temperature?

    6. Define dew point temperature?

    7. Define Relative Humidity (RH) AND Specific humidity?

    8. Differentiate between absolute and relative humidity.

    9. Define DPT and degree of saturation?.

    10. What is dew point temperature?

    11. On a psychometric chart, show all the property lines?

    12. Show the dew point and adiabatic saturation process n a skeleton T-s diagram of

    Water?

    13. State Daltons law of partial pressure?

    14. Define Apparatus Dew Point (ADP) of cooling coil?15. List down the psychrometric processes?

    16. Define Bypass factor of a coil?

    17. Define the humidification process?

    18. State the effects of very high and a very low bypass factor?

    19. What factors affect by pass factor?

    20. What are the assumptions made while mixing two air streams?

    21. Represent the following psychrometric processes using a skeleton psychrometric

    Chart?

    21.What is dew point Depression?

    22.What is adiabatic saturation temperature?23.What are the substances used in chemical dehumidification?24.What is sensible heat?25.What is latent heat?26.How does humidity affect human comfort?27.What is meant by adiabatic mixing?28.Define sensible heat factor?29.Show the dew point and adiabatic saturation process on T-s diagram of water?30.What is Wet bulb Depression?31.What is meant by apparatus dew point temperature?

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    32.Define RSHF?33.What is Psychrometer?34.Define GSHF?35.Define chemical dehumidification?36.

    What is adiabatic evaporative cooling?37.Define adiabatic mixing of two streams?

    38.What is infiltration air load?39.What is equipment load?40.What is fresh air load?

    UNITV (PARTB)

    1. Give short notes on following(a) Specific humidity (b) Relative humidity (c) Dew point temperature (d) Wet bulb

    depression

    2. Explain adiabatic saturation process?3. Explain bypass factor of cooling coil and state its effects?4. In an adiabatic mixing of two streams, derive the relationship among the ratio of

    enthalpy change and ratio of specific humidity change?

    5. Air has a dry bulb temperature of 250C and wet bulb temperature of 150C. If thebarometer reads 1bar, Calculate

    (a)Vapour pressure(b)Specific humidity(c)Saturation ratio(d)Relative humidity(e)Dew point temperature(f) Vapour density(g)Enthalpy of mixture.

    6. An air water mixture at 200C and 1 bar has relative humidity 80% Calculate(a)Partial pressure of the vapour and the air(b)Specific humidity(c)Saturation ratio(d)Dew point temperature(e)Density of air(f) If the mixture is cooled at constant pressure to a temperature of 100C, find the

    amount of watervapour condensed / kg of dry air?

    7. The atm air has a dry bulb temperature of 200C and the specific humidity of0.0095kg/kg of dry air. If the barometer reads 760mm of Hg, determine

    (a)Partial pressure of the vapour(b)Relative humidity(c)Dew point temperature.

    8. The sling psychrometer in a laboratory test recorded the following readingsDry bulb temperature = 250C, Wet bulb temperature = 150C,

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    Barometer readings = 760 mm of Hg, Partial pressure = 10 mm of Hg,

    Determine the specific humidity and saturation ratio?

    9. A mixture of air and water vapour possesses a volume of 700m3 at 1 pressure andtemperature 350C. Its relative humidity is 75%. Find the specific humidity, dew point

    temperature, mass of air and mass of vapour in the mixture?10.Atmospheric air at 76cm of Hg has 250C dry bulb temperature and 150C wet bulbtemperature using Psychrometric chart Calculate the following

    (a)Relative humidity(b)Humidity ratio(c)Dew point temperature(d)Enthalpy(e)Partial pressure of water(f) Specific volume of air(g)Saturation pressure corresponding to dry bulb temperature.(h)Saturation pressure corresponding to wet bulb temperature.

    11.Atmospheric air at 1bar pressure has 300C dry bulb temperature and 50% relativehumidity. Using psychrometric chart calculate the dew point temp, enthalpy and

    vapour pressure?

    12.An air conditioning system is designed under the following condition:Out door condition - 350C DBT and 70% RH

    Required indoor condition250C DBT and 75% RH

    Amount of fee air circulated250m3/min

    Coil dew point temperature150C

    The required condition is achieved by first cooling and dehumidification. Calculate theCapacity of cooling coil in TOR, Capacity of heating in kW, Mass of water vapour

    removed in kg/sec.

    13.2kg of air at 300C, 65% RH is mixed adiabatically with 5kg of air at 20 0C, 10%RH.Determine final condition of the mixture?

    14.Air at 20C, 40% RH is mixed with adiabatically with air 400C, 40% RH in the ratio of1kg of the former with 2kg of the later (on the dry basis) Find the final condition?

    15.An air water vapour mixture at 0.1Mpa, 300C, 80% RH has a volume of 50m3.Calculate the specific humidity, dew point temp, Mass of dry air and mass of water

    vapour?