Which one of the following engines will have heavier flywheel than the remaining ones?
A. 30 kW four-stroke petrol engine running at 1500 r.p.m.
B. 30 kW two-stroke petrol engine running at 1500 r.p.m.
C. 30 kW two-stroke diesel engine running at 750 r.p.m.
D. 30 kW four-stroke diesel engine running at 750 r.p.m.
Answer: Option C
Solution(By Examveda Team)
The flywheel's weight is primarily determined by the engine's firing frequency, which is related to the number of power strokes per minute. Since the two-stroke diesel engine has the lowest number of power strokes per minute (750 r.p.m.), it will experience larger fluctuations in torque between power strokes, necessitating a heavier flywheel to smooth out these fluctuations.The heavier flywheel is required for engines with lower firing frequencies (lower RPM) to help smooth out power delivery and reduce vibration. Since both Options C and D have the same RPM (750 r.p.m.), we need to consider the type of engine.
The two-stroke diesel engine tends to have more vibration compared to a four-stroke engine due to its firing frequency and fewer cycles to absorb the power strokes. Therefore, the two-stroke diesel engine (Option C) will likely require a heavier flywheel compared to the four-stroke diesel engine (Option D).
Hence, the correct answer is: Option C: 30 kW two-stroke diesel engine running at 750 r.p.m.
This Question Belongs to Mechanical Engineering >> Internal Combustion Engines (I.C. Engines)
Join The Discussion
Comments ( 5 )
Engine pistons are usually made of aluminium alloy because it
A. Is lighter
B. Wear is less
C. Absorbs shocks
D. Is stronger
The reason for supercharging in any engine is to
A. Increase efficiency
B. Increase power
C. Reduce weight and bulk for a given output
D. Effect fuel economy
Morse test can be conducted for
A. Petrol engines
B. Diesel engines
C. Multi cylinder engines
D. All of these
The cetane (C16H34) which is a straight chain paraffin, is assigned a cetane number of
A. 0
B. 50
C. 100
D. 120
Option d is the correct answer not a.
Option d..Amal nalinam reason right
Option D is the answer because slow speed engine will have heavier flywheel.
right amal nalinam
Optin D is the answer. For the same energy developed, a slow speed engine has a heavier flywheel and compared to petrol engines, for the same amount of power developed, the diesel engine has a heavier flywheel.