更多"The two strokes of a two-stroke/cyc"的相关试题:
[单项选择]A disadvantage of a four-stroke/cycle diesel engine is （）
A. higher working temperature of piston and cylinder
B. the use of scavenge ports
C. fewer power strokes per revolution of the crankshaft
D. part of the fuel is burned as the piston is moving away from top dead center
[单项选择]In a single acting, four-stroke/cycle diesel engine, the power impulse in an individual cylinder occurs （）
A. once every crankshaft revolution
B. once every two crankshaft revolutions
C. once every piston stroke
D. twice every piston stroke
[单项选择]The marine diesel engine is a type of diesel engine used on ships The （） of its operation is not very difficult to understand.
A. principle
B. principal
C. cause
D. case
[单项选择]Increasing the compression ratio of a diesel engine while maintaining the designed rate of fuel flow will result in （）
A. increased horsepower
B. reduced efficiency
C. increased heat loss
D. lower cylinder pressures
[单项选择]The exhaust system for a turbocharged diesel engine functions to （）
A. power the after-coolers
B. power the turbocharger
C. reduce the cylinder scavenge effect
D. cool the turbocharger
[单项选择]When transmitted by a reduction gear, diesel engine speed is reduced and the torque available for work （）
A. remains the same
B. is reduced
C. is increased
D. is eliminated
[单项选择]Starting a large low-speed propulsion diesel engine on diesel fuel during cold weather conditions, will be made easier by （）
A. increasing the quantity of starting air
B. increasing the lube oil pressure
C. heating the engine fuel supply
D. heating the engine coolant
[单项选择]The over-speed trip installed on most diesel engine will stop the engine by shutting off the （）
A. water supply
B. fuel oil supply
C. lube oil supply
D. exhaust damper
[单项选择]Due to excessive water in the fuel, a diesel engine fails to startBefore the engine can be started, the water must be removed from the （）.
A. fuel pumps
B. cylinders
C. fuel strainers
D. all of above
[单项选择]Critical speed in diesel engines occurs when engine torque pulsations become （）
A. opposed to the crankshaft rocking couple
B. resonant with the crankshaft natural frequency
C. critical fore and aft crankshaft vibrations
D. horizontal whipping motions of the crankshaft
[单项选择]Oil control rings used in two-stroke/cycle diesel engines are located near the bottom of the piston skirt in order to （）
A. increase the liner area covered by the oil film
B. maintain an oil film on the lower liner where scuffing is prevalent
C. keep excess oil away from intake and exhaust ports
D. help cushion piston skirt side thrust by providing a hydrodynamic oil wedge
[单项选择]A two-stroke/cycle diesel engine requires less starting air than a four-stroke/cycle diesel engine, of equal displacement, because the two-stroke/cycle diesel engine（）
A. has little or no internal friction
B. has a lower effective compression ratio
C. operates with scavenge air under a positive pressure
D. operates without energy absorbing intake and exhaust strokes
[单项选择]A disadvantage of a two-stroke/cycle diesel engine is（）
A. more power strokes per revolution
B. the use of scavenge air
C. more complicated valve gear
D. higher working temperature of the piston and cylinder
[单项选择]In the cylinder head of a two-stroke/cycle diesel engine, valves are used for（）
A. air intake
B. a fuel outlet
C. cooling water inlets
D. exhausting combustion gas
[单项选择]The intake ports of a two-strike/cycle diesel engine are opened and closed by the action of the （）
A. camshaft
B. piston movement
C. exhaust valves
D. vertical drive
[单项选择]A large two-stroke/cycle direct reversing diesel engine is to be reversedPrior to the admission of starting air you must （）
A. line up the engine fore restarting with light diesel oil
B. reposition the fuel injection cam
C. change the intake and exhaust valve cam positions
D. place the starting cam in the intermediate position
[单项选择]A six-cylinder, two-stroke/cycle diesel engine is fitted with a rotary distributing air starting systemThe speed of the rotating distributor disc is （）
A. one-half engine speed
B. the same as engine speed
C. twice engine speed
D. four times engine speed
[单项选择]In a two-stroke/cycle diesel engine, the exhaust gases are expelled from the cylinder by the（）
A. exhaust manifold
B. valve bridge
C. pressure of the fresh air charge
D. valve adjusting gear
[单项选择]In a single acting, two-stroke/cycle, diesel generator engine, the power impulse in an individual cylinder occurs （）
A. once every crankshaft revolution
B. once every two crankshaft revolutions
C. once every piston stroke
D. twice every piston stoke
