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单选题
How does combustion air enter the cylinder of a two-cycle diesel engine?（）
A
Cylinder head valves
B
Ports
C
Turbo chargers
D
Bleeder valves
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If the exhaust gas temperature of the incinerator is too high, or if sparks are developed, What should you do?
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考题
If the engine does start on air, but combustion does not immediately begin, the cause may be _____.A.failure of the fuel pumpsB.starting air pressure too lowC.stop valve in air line closedD.the turning gear still engaged
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Diesel engines obtain combustion air through turbo chargers，blowers，or ______．A.Air startersB.CarburetorsC.Natural aspirationD.Air receivers
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How does combustion air enter the cylinder of a two-cycle diesel engine ? Through _______．A.Cylinder head valvesB.PortsC.Turbo chargersD.Bleeder valves
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单选题The primary purpose of oil control rings on a diesel piston is to（）A
provide a reservoir for cylinder lubricationB
pump oil into the combustion space for cylinder coolingC
prevent excessive lubricating oil consumptionD
allow hydraulic oil film formation on the cylinder
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单选题The most practical way of detecting an overload in one cylinder of an operating large, low-speed ,main propulsion diesel engine is to （）A
check the cylinder exhausts for black smokeB
listen for combustion knock in that cylinderC
isolate each cylinder and inspect the injectorD
check the cylinder exhaust temperature frequently
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单选题The term diesel engine scavenging means（）A
delivering more air into the cylinder than it would normally receive during an ordinary charging processB
forcing the products of combustion out of the cylinder with the fresh air chargeC
collecting the air charge at the cleanerD
combustion and expansion of hot gas
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单选题If the engine does start on air, but combustion does not immediately begin, the cause may not be （）.A
low compressionB
failure of the fuel pump to discharge fuelC
incorrect timing of fuel pumpD
turning gear being still on
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单选题Gas exchange, which is a basic part of the cycle of an internal combustion engine, is（）A
the supply of normal air and removal of compressed airB
the supply of fuel oil and combustion of the atomized oilC
the supply of fresh air and removal of exhaust gasesD
the supply of fresh air and removal of the extra heat
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单选题Compressed air is supplied by air compression to （）.A
the air receiversB
the starting valvesC
the cylinder coversD
the distributors
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单选题The cylinder head, cylinder liner and （） form the combustion chamber.A
frameB
pistonC
crankcaseD
explosion plate
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单选题In an engine with air inlet valve and exhaust valve on its cylinder heads the fresh air will enter into the cylinder （） and the gases exhaust （）, there being an adequate overlap between the inlet opening and the exhaust closing.A
downwards；upwardsB
upwards；downwardsC
downwards；downwardsD
upwards；upwards
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单选题The longer the ignition delay period resulting from improper use of low cetane fuel, the （）A
less fuel will enter the cylinderB
higher the cylinder combustion temperatureC
more complete the fuel combustionD
more rapid the rise in combustion pressure
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单选题The longer the ignition delay period occurs in a diesel engine, the （）.A
less fuel will enter the cylinderB
lower will be cylinder compression temperaturesC
more complete will be fuel combustionD
more rapid will be the rise in combustion pressure
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单选题If the engine does start on air, but combustion does not immediately begin, the cause may be （）.A
failure of the fuel pumpsB
starting air pressure too lowC
stop valve in air line closedD
the turning gear still engaged
考题
单选题（） supplies pilot air to control the cylinder air start valves.A
An air compressorB
An indicator cockC
An air distributorD
A safety valve
考题
单选题Which statement about diesel engine combustion is true?（）A
Combustion does not begin until the piston starts down on the power strokeB
Maximum combustion pressure is reached before TDCC
Turbulence in the cylinder causes a delay in ignitionD
Maximum cylinder firing pressure is not developed until the piston passes TDC
考题
单选题For a given size engine, the two-stroke/cycle diesel engine will deliver more power than a four-stroke/cycle diesel engine because （）.A
it has a longer power strokeB
more air gets into the cylinder each strokeC
it develops twice as many power strokes at the same speedD
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单选题Fuel droplets injected into a diesel engine cylinder must have adequate penetration to （）A
prolong the ignition delay periodB
ensure the beginning of fuel injectionC
thoroughly utilize the air chargeD
allow controlled fuel combustion
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单选题Turbocharged four-stroke/cycle diesel engines utilize valve overlap for（）.A
improving cylinder scavengingB
preheating the combustion chamberC
reducing air charge densityD
preventing valve wear
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单选题The air required for combustion is taken from the engine room through a filter fitted on the turbochargerThis reduces the risk for too and contamination of the combustion air（）A
high temperaturesB
low temperaturesC
wetD
dirty
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单选题Fuel injection systems meter fuel, atomize fuel, and （）.A
create turbulence in the combustion chamberB
aid in completing cylinder scavengingC
inject fuel at the proper timeD
minimize fuel penetration into the cylinder
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单选题If an air compressor is used to supply air primarily to the combustion control system and other pneumatic controllers, the entire system is known as the （）.A
control air systemB
forced draft air systemC
supply air systemD
ships service air system
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单选题Proper dispersion of fuel in a diesel engine cylinder is dependent upon the （）A
injection pressureB
shape of combustion spaceC
turbulence in combustion spaceD
all of the above
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单选题The exhaust ports are located around the lower part of the cylinder liner, （）the products of combustion are driven by scavenging air.A
in whichB
by whichC
through whichD
from which
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