why four stroke diesel engine inlet valve is bigger than exhaust valve

by Guest8714  |  8 years, 11 month(s) ago

1 LIKES UnLike

please anyone who know answer this question

 Tags: bigger, diesel, Engine, exhaust, inlet, stroke, Valve



  1. Guest6493
    The fuel/air mixture volume needs to be high on the intake stroke. When both valves are closed the piston is rising (compression stroke), at the top of the compression stroke, the spark plugs fires, igniting the fuel mixture. The confined fuel mixture which is under pressure begins to slowly burn causing a sharp increase in the temperature. If gases in a confined space increases in temperature, there is an equally proportional increase in pressure as well due to the expansion of the gases. (Law and properties of gases) This increases cylinder pressure forcing the piston downward (power stroke.) At the bottom of the power stroke the exhaust valve opens and the intake remains closed (exhaust stroke). Since the air/fuel mixture has decreased in volume (along with the increase of the confined space) there is now very little pressure in the cylinder so the piston has a much smaller volume of gases to push out during the exhaust stroke and the need for a larger valve is not required. (decreasing the cost of manufacturing the engine)

Sign In or Sign Up now to answser this question!

Question Stats

Latest activity: 10 years, 4 month(s) ago.
This question has 1 answers.


Share your knowledge and help people by answering questions.
Unanswered Questions