Consider the following statements regarding supercharging of Diesel engines: 1) The mechanical efficiency of a supercharged diesel engine is slightly better than that of the naturally aspirated engine. 2) There is a reduction in smoke in the case of a supercharged engine in the overload operation. 3) Increased valve overlap is used in the supercharged engine. Which of the above statements are correct?

1, 2 and 3
1 and 2 only
1 and 3 only
2 and 3 only

LohaHridoy

4 views

2025-01-04 04:42

1 Answers

AhmedNazir

Option 1 : 1, 2 and 3

Explanation:

Supercharging of diesel engine increases mechanical efficiency despite the increase in friction power due to a large increase in brake mean effective pressure or equivalently we can say due to the large increase in brake power.
The reduction of smoke in the super-charged engine at overload is due to the availability of oxygen in sufficient quantity. In a naturally aspirated engine, this level of smoke is high.
Due to supercharging heat generation and heat transfer increases.
As a result of which there is a greater tendency of overheating the piston crown and the seat and edges of exhaust valves.
To overcome this problem the valve overlap is greater.

Hence all the statements 1,2 and 3 are correct. So, the correct option is an option (1)

4 views Answered 2022-09-04 04:29

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