Question

1. A 12-cylinder, 4-stroke automobile engine is being designed. What type of cylinder arrangement would you recommend? (a) In-Line (b) V-Type (c) W-Type (d) Rotary. 2. The expression "cylinder cut-out" means : (a) Half of cylinder volumes is used. (b) Half of cylinder numbers is used. (c) Half of cylinder masses is used. (d) None of the above. 3. Adding lubrication oil to the inlet fuel- air mixture in 2-st engines will increase: (a) HC emissions. (b) CO emissions (c) NO, emissions. (d) (a) and (b). 4. The cetane number of a diesel fuel indicates: (a) Fuel resistance to self-ignition. (b) The ignition delay time. (c) The energy content of the fuel. (d) All of the above. 5. In 2-st engines, the piston is usually designed to have a deflector to : (a) Reduce the inlet charge pressure. (b) Reduce the inlet charge velocity. (c) Direct the inlet charge inside the cylinder. (d) Increase the inlet charge velocity. 6. Carbon deposits build-up on the combustion chamber walls can cause: (a) Pre-ignition. (b) Increase in cylinder temperature. (c) Increase in compression ratio. (d) All of the above. 7. The main disadvantage of turboprop 8. All of the following are considered engines compared with propeller engines is alternative fuels for ICES EXCEPT: (a) Low cursing speed. (a) Methanol. (b) Low fuel consumption. (b) Natural gas. (c) Low altitude level. (c) Bio-fuels. (d) High weight to thrust ratio. (d) Tetraethyl lead. 9. A time variation under steady-state engine conditions where the air/fuel ratio in a given cylinder varies is called: (a) Stroke-by-stroke variation. (b) Cycle-by-cycle variation (e) Cylinder-by-cylinder variation. (d) Engine-by-engine variation. 10. In some engine designs, the intake manifold is heated slightly, which results in: (a) Reduce the volumetric efficiency. (b) Accelerate the fuel evaporation (c) Increase the combustion temperature. (d) All of the above. 11. At high engine temperature, the end gas can explode before the ignition time in SIEs. This is called: (a) Ignition (b) Combustion. (c) Compression (d) Detonation 12. The self-ignition temperature of a diesel fuel........than that of petrol fuel: (a) is higher. (b) is lower. (c) is the same. (d) depends on fuel quality.

Answer 1

Answers :

1) V-type

2) Half of cylinder volume is used.

3) (a) and (b)

4) the ignition delay time

5) Increase the inlet charge velocity

6) All of the above

7) low altitude level

8) Tetraethyl lead

9) cycle by cycle variation

10) accelerate the fuel evaporation

11) detonation

12) is lower

Explanation :

D A 12. cylinder, anstrobe automobile engine is being - designed. What type of auangement would you recommended? TV-type .. 3) Adding lubrication ou to the inlet fuel-ecir 1. Misture in dost engines will increase ] (a) and (b) I live eminitions and to emission] - In aust engines, the piston is usually designed to have a deflector to Increase the inlet charge velocity / •7) The main disadvantage of turboprop engines compared - with propellen engines abis [Low altitude load] 9) A time-variation under steady-state engine conditions - where the airffuel ratio in a given cylindes varies 1. is called how ath [cycle by cycle variation ! 11). At high engine temperature, the end gas can = explode before the ignition time in SIES . This is called Detonation (92) The expression "Cylincles cut out" means Hall of cylineler volume is used 4) The catane number of a diesel fud indicator is the ignition delay time)

6) Carbon deposits build up on the combustion Chamber walls on cause all of the above j [Pre-ignition, Increase in cylinder temperature, Inreare in compression vakio ] 8 All of the following are considered alternative - fuels for IEs except | Tetraethyl lead ] 16) In some engine designs, the intake manifold - is heated slightly which results isn (Acederate the fuel evaporation. 12) The sey-ignition temperature of a diesel fuel as lower] then the petrol fuel.