Describe four effects of detonation.

Describe four effects of detonation.
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1 Answer

Answer :

1. Noise and roughness: Mild knock is seldom audible and is not harmful. When intensity of knock increases a loud pulsating noise is produced due to development of a pressure wave. The presence of vibratory motion causes crankshaft vibrations and engines rough. 2. Mechanical damage: Due to rapid pressure waves, rate of wear is increased and piston head, cylinder head and valves may be pitted. 3. Carbon deposits: Detonation results in increased carbon deposits. 4. Increase in heat transfer: Temperature in detonating engine is higher as compared to non detonating engine and hence scoring away the protecting layer of inactive stagnant gas. So detonation increases the rate of heat transfer to combustion chamber walls. 5. Decrease in power output and efficiency: Due to increase in the rate of heat transfer the power output is decreased. 6. Pre ignition: Detonation results in over heating of the sparking plug and combustion chamber wall and this overheating leads to ignite the charge before the passage of spark.
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