In a diesel engine, the ignition is initiated by the:
Show Hint
- spark
- preheating of the fuel
- heating due to the compression of intake air
- preheating of the intake air
The Correct Option is C
Solution and Explanation
Step 1: Understanding diesel ignition.
In a diesel engine, only air is compressed inside the cylinder. This compression raises the air temperature to a very high value (typically 500–700°C).
Step 2: Role of fuel injection.
Fuel is injected near the end of the compression stroke. The fuel droplets enter the hot compressed air and ignite spontaneously without any spark.
Step 3: Conclusion.
Ignition is caused by the heating due to compression of intake air, making option (C) correct.
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