Question

Towards the end of the compression stroke when injection of the fuel into the combustion chamber commences, the quantity of fuel discharged is spread out over a predetermined period.

(a) True

(b) False

This question was addressed to me in class test.

This intriguing question comes from Combustion in C.I. Engine topic in division Combustion and Combustion Chambers of IC Engine

Answer 1

The correct answer is:

(a) True

Explanation: In Compression Ignition (C.I.) engines, the fuel injection process typically begins towards the end of the compression stroke, right before the piston reaches the top dead center (TDC). The injection of fuel is not instantaneous but is spread out over a predetermined duration. This is done to optimize combustion and ensure smooth operation, controlling factors like fuel atomization, mixing with air, and avoiding excessive pressure spikes. The duration and timing of injection are carefully controlled to match engine performance requirements and emissions standards.