Important RGPV Question
ME-501 IC ENGINES
V Sem, ME
UNIT 1-Introduction of IC Engine
Q.1) Differentiate between 4-Stroke and 2-Stroke Engine.
(RGPV June 2023)
Q.2) What are the requirements for spark plug?
(RGPV June 2023)
Q.3) Explain stages of combustion in CI engines.
(RGPV June 2023)
Q.4) In a Trial of single cylinder diesel engine the following observations were made:
Calorific value of fuel = 43890 kJ/kg. , Oil consumption = 10.2 kg/h, Speed = 1900 rpm, Air consumption = 3.8 kg/min, compression ratio = 15, Torque 186 Nm. , Quantity of cooling water used = 15.5 kg/min, Temp, rise = 36°C, Exhaust gas temp = 410°C, Room Temp = 20°C, Cp of exhaust gases = 1.17 KJ/kg K
Calculate:
i) B.P.
ii) BSFC
iii) Heat Balance sheet on minute basis
(RGPV June 2023)
Q.5) What are the factors effecting the volumetric efficiency of spark ignition and compression ignition engine?
(RGPV June 2020)
Q.6) Define the performance parameters of IC engine i.e indicated power, mean effective pressure, indicated thermal efficiency, brake power, mechanical efficiency.
(RGPV June 2020)
Q.7) In air standard Otto-cycle, the compression ratio is 10. The condition at the beginning of the compression process is 100 kPa and 27°C. Heat added at constant volume is 1500 kJ/kg, while 700 kJ/kg of heat is rejected during the other constant volume process in the cycle. Specific gas constant for air = 0.287 kJ/kg K. Find the mean effective pressure (In kPa) of the cycle.
(RGPV June 2020)
Q.8) Explain Wankel engine with neat sketch.
(RGPV June 2023)
Q.9) Compare spark ignition and compression ignition engine. Write the difference between auto and diesel engine.
i) Bore ii) Stroke
iii) Displacement volume iv) Clearance volume
v) Compression ratio vi) Cubic capacity
(RGPV Dec 2020)
(RGPV Dec 2020)
UNIT 2-Combustion in SI Engines
Q.1) A perfect gas at 1 bar and 290 K undergoes ideal diesel cycle. The maximum pressure of the cycle is 50 bar. The volume at the beginning of compression is 1m³ and after constant pressure heating is 0.1m³. Determine the temperature at all salient pressure heating is 0.1m³. Determine the temperature at all salient points of the cycle and find out the efficiency of the cycle. Take y = 1:4 for the gas.
(RGPV June 2023)
Q.2) What is Scavenging? Explain various types of scavenging.
(RGPV June 2023)
Q.3) Explain the types of combustion chambers used in SI engines and compare them. Why maximum diameter of SI engine combustion chambers is limited.
(RGPV June 2020)
Q.4) Explain the various stages of combustion in spark ignition engine and draw the Pressure-Crank angle diagram.
(RGPV June 2020)
Q.5) Explain with a neat diagram of the various methods of scavenging process. What do you understand by ignition living? Discuss various factors which affect the ignition timing.
(RGPV June 2020)
Q.6) What do you mean by normal and abnormal combustion? Discuss the detonation theories of S.I. engine. Enlist variables affecting detonation in S.I. engine.
(RGPV June 2020)
Q.7) Briefly explain the stages of combustion in SI engines elaborating the flame front propagation.
(RGPV Dec 2020)
Q.8) Explain with sketch working of battery ignition system with its advantages and disadvantages.
(RGPV June 2023)
Q.9) In a SI engine working on ideal auto cycle, the compression ratio is 5.5. The pressure and temperature at the beginning of compression are 1 bar and 27°C respectively. The peak pressure is 30 bar. Determine the pressure and temperatures at the salient points, the air standard efficiency and the mean effective pressure. Assume ratio of specific heats to be 1.4 for air.
(RGPV Dec 2020)
UNIT 3-Combustion in CI Engines
Q.1) The dimensions of carburetor are as follows. Venturi throat diameter is 20 mm with coefficient of discharge of 0.85, Fuel orifice diameter is 1.25 mm with coefficient of fuel flow of 0.66, the fuel surface is 5mm below the throat. Compute
i) Air fuel ratio for depression of 0.07 bar when nozzle lip is neglected.
ii) Air-fuel ratio when nozzle lip is considered.
(RGPV June 2023)
Q.2) Different types of nozzles in Diesel fuel injection systems.
(RGPV June 2023)
Q.3) A six cylinder four stroke engine develops 200 kW at 1200 rpm and consumes 0.3 kg/kWh. Determine the size of the single hole injector nozzle if the injection pressure is 160 bar and pressure in combustion chamber is 40 bar. The period of injection is 30° of crank angle. Specific gravity of fuel is 0.85 and orifice discharge coefficient is 0.7.
(RGPV June 2020)
Q.4) Explain with a neat diagram the principle, construction and working of MPFI system.
(RGPV June 2020)
Q.5) Write short note on Solex carburetor. Discuss different types of cooling systems of I.C. engine.
(RGPV June 2020)
Q.6) Define carburetion. Explain the following Rich mixture, Stoichiometric mixture and lean mixture.
(RGPV Dec 2020)
Q.7) Describe with suitable sketches of the following systems
of a modern carburetor:
i) Main metering system
ii) Idling system
iii) Economizer system
iv) Acceleration pump system
v) Choke
(RGPV Dec 2020)
Q.8) Explain the phenomenon of knock in CI engines and compare it with SI engine Knocks.
(RGPV Dec 2020)
Q.9) Explain with figures various types of combustion chambers used in CI engines.
(RGPV Dec 2020)
Q.10) Give a brief account of emissions of CI engines.
(RGPV Dec 2020)
UNIT 4-Fuel
Q.1) Write the short note on Alternate fuels in IC engines.
(RGPV June 2023)
Q.2) How will you classify the I.C. engine fuels? Describe the characteristics of SI and CI engine fuels.
(RGPV June 2020)
Q.3) What are the various alternative fuels for SI and CI engines? Differentiate LPG and CNG.
(RGPV June 2020)
Q.4) What are the different kinds of fuels used in an IC engine?
Briefly explain the petroleum refining processes.
(RGPV Dec 2020)
Q.5) Give the general chemical formula of the following fuels:
i) Paraffin ii) Olefin
iii) Naphthene iv) Aromatic
Also state their molecular arrangements and mention
whether they are saturated and unsaturated.
(RGPV Dec 2020)
Q.6) Exhaust gas re-circulation advantage and limitations, with neat sketch.
(RGPV June 2023)
(RGPV Dec 2020)
Q.8) What are Homogeneous and Heterogeneous Mixtures? In which engines these mixtures are used? Explain.
(RGPV Dec 2020)
UNIT 5-Supercharging & Turbo charging
Q.1) Explain any one type of cooling system in engine with its advantages.
(RGPV June 2023)
Q.2) What is super charging and turbo charging? Describe in brief the methods of turbo charging.
(RGPV June 2023)
Q.3) What are the advantages of microprocessor-based control system for automobile? What is the disadvantage of microprocessor controlled devices?
(RGPV June 2023)
Q.4) Explain why turbocharged engines may have inferior values of power output and fuel consumption than naturally aspirated engines especially at low speed.
(RGPV June 2020)
Q.5) What are the different functions of lubricating system? State the different lubricating systems used for IC Engines. Explain any one of them.
(RGPV June 2020)
Q.6) Clearly explain the various wet sump lubrication system. Compare wet sump and dry sump lubrication system.
(RGPV Dec 2020)
Q.7) Explain only two of the following:
i) Thermosyphon cooling system
ii) Forced circulation cooling system
iii) Evaporative cooling system
(RGPV Dec 2020)
Q.8) What are the factors that affect the power output of an engine? Explain how super charging help the power output.
(RGPV Dec 2020)
— Best of Luck for Exam —
