单选题Air scavenging of a diesel engine cylinder（）A blows out the exhaust gasesB supplies oxygen for combustionC cools the valves and cylinder wallsD all of the above

题目
单选题
Air scavenging of a diesel engine cylinder（）
A

blows out the exhaust gases

B

supplies oxygen for combustion

C

cools the valves and cylinder walls

D

all of the above

相似考题

1.Exhaust gases are generally removed from the cylinders of a two-stroke/cycle diesel engine byA.natural aspirationB.masked intake valvesC.air ceilsD.scavenging air

2.Which of the following conditions could contribute to the cracking of a diesel engine cylinder head?A.Leaking seal ringB.Insufficient heat transfer from the exhaust valvesC.Blocked cooling water passages to the headD.Excessive scavenging air provided to the engine

3.In an operating diesel engine, which of the following conditions is an indication of a leaking air starting valve?A.Noise coming from that air starting valveB.Continuous operation of the starting air compressorC.Zero air pressure in the air starting systemD.Overheated starting air pipe to the cylinder head

4.A two stroke diesel engine exhaust temperature will be lower than a four stroke diesel engine of the same displacement because the _____. ① MEP is lower and the scavenging air is cooling the exhaust gases ② valve overlap in a four strokeA.①B.②C.① and ②D.Neither ① nor ② is correct

更多“Air scavenging of a diesel engine cylinder（）”相关问题

  • 第1题：

    How does combustion air enter the cylinder of a two-cycle diesel engine ? Through _______．

    A.Cylinder head valves

    B.Ports

    C.Turbo chargers

    D.Bleeder valves


    正确答案：B

  • 第2题：

    单选题
    Air motion is induced in a four-stroke/cycle diesel engine cylinder to improve air fuel mixing, and is known as（）
    A

    supercharging

    B

    scavenging

    C

    turbulence

    D

    swept volume charging


    正确答案： C
    解析： 暂无解析

  • 第3题：

    单选题
    When an air started, four-stroke/cycle diesel engine is being cranked, the starting air is admitted to each cylinder during what would normally be the（）
    A

    intake stroke

    B

    compression stroke

    C

    power stroke

    D

    exhaust stroke


    正确答案： A
    解析： 暂无解析

  • 第4题：

    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 process

    B

    forcing the products of combustion out of the cylinder with the fresh air charge

    C

    collecting the air charge at the cleaner

    D

    combustion and expansion of hot gas


    正确答案： B
    解析： 暂无解析

  • 第5题：

    单选题
    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


    正确答案： D
    解析： 暂无解析

  • 第6题：

    单选题
    Any increase in the exhaust back pressure of a four-stroke/cycle diesel engine will （）.
    A

    reduce engine horsepower output

    B

    aid in silencing the exhaust noise

    C

    increase the mean effective pressure

    D

    contribute to effective cylinder scavenging


    正确答案： C
    解析： 暂无解析

  • 第7题：

    单选题
    Heat for igniting the fuel oil in the cylinder of a diesel engine is generated by the （）
    A

    electronic ignition system

    B

    compression of air by the piston

    C

    friction in the fuel injector

    D

    fuel oil bearing system


    正确答案： C
    解析： 暂无解析

  • 第8题：

    单选题
    The process of scavenging a two-stroke/cycle diesel engine serves to（）
    A

    improve fuel flow volume

    B

    cool the exhaust valves

    C

    reduce the intake air charge density

    D

    increase the temperature of exhaust gases


    正确答案： B
    解析： 暂无解析

  • 第9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 stroke

    B

    more air gets into the cylinder each stroke

    C

    it develops twice as many power strokes at the same speed

    D

    higher combustion pressure is developed


    正确答案： D
    解析： 暂无解析

  • 第10题：

    单选题
    The highest pressure in a diesel engine cylinder normally occurs （）.
    A

    at TDC

    B

    before TDC

    C

    after TDC

    D

    during air starting


    正确答案： A
    解析： 暂无解析

  • 第11题：

    单选题
    Compared to a naturally aspirated diesel engine, a supercharged diesel engine has（）
    A

    a cylinder air charge of higher pressure

    B

    increased pumping losses

    C

    less valve overlap

    D

    reduced blow-by


    正确答案： C
    解析： 暂无解析

  • 第12题：

    单选题
    The timing of diesel engine air starting valves is controlled by（）
    A

    the air start valve timing gears and rods

    B

    a cylinder check valve

    C

    individual cams and valve gear

    D

    an air manifold poppet valve


    正确答案： D
    解析： 暂无解析

  • 第13题：

    单选题
    Which of the following conditions could contribute to the cracking of a diesel engine cylinder head?（）
    A

    Leaking seal ring

    B

    Insufficient heat transfer from the exhaust valves

    C

    Block cooling water passages to the head

    D

    Excessive scavenging air provided to the engine


    正确答案： C
    解析： 暂无解析

  • 第14题：

    单选题
    Why are some diesel engine cylinder liners plated on the wearing surface with porous chromium?（）
    A

    The chromium will not wear out the piston rings

    B

    The chromium strengthens the liners in the way of the scavenging air ports

    C

    Chromium eliminates the need for oil scraper rings

    D

    Pores in the plating aid in maintaining the lube oil film


    正确答案： C
    解析： 暂无解析

  • 第15题：

    单选题
    A drop in compression pressure in one cylinder of a diesel engine can be caused by（）
    A

    a leaking fuel injection nozzle

    B

    a clogged air filter

    C

    early fuel injection

    D

    burned valves


    正确答案： B
    解析： 暂无解析

  • 第16题：

    单选题
    "Scavenging" on a diesel engine means （）.
    A

    injecting fuel oil into a cylinder

    B

    removing exhaust gases from the cylinder

    C

    forcing air into the cylinders under pressure after the exhaust valve has dosed

    D

    a combination of all the above


    正确答案： A
    解析： 暂无解析

  • 第17题：

    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


    正确答案： B
    解析： 暂无解析

  • 第18题：

    单选题
    In a two-stroke engine, there are always a series of openings known as （）, and in some circumstances, there are also openings known as （）, in the part of the cylinder liner.
    A

    scavenging air ports；exhaust ports

    B

    inlet ports；scavenging air ports

    C

    scavenging air ports；inlet ports

    D

    exhaust ports；inlet ports


    正确答案： A
    解析： 暂无解析

  • 第19题：

    单选题
    The purpose of compressing the air within the cylinder of a diesel engine is to （）
    A

    produce the heat for ignition

    B

    decrease injection lag

    C

    increase ignition delay

    D

    aid in exhausting burnt gases


    正确答案： C
    解析： 暂无解析

  • 第20题：

    单选题
    The principal difference between loop scavenging and crossflow scavenging, as used in single acting diesel engines, is the （）
    A

    direction of air flow within the cylinder

    B

    sequence of port opening

    C

    method of opening exhaust ports

    D

    volume of air admitted to the cylinder


    正确答案： C
    解析： 暂无解析

  • 第21题：

    单选题
    In an operating diesel engine, which of the following condition is an indication of a leaking air starting valve?（）
    A

    noise coming from that air starting valve

    B

    continuous operation of the starting air compressor

    C

    zero air pressure in the air starting system

    D

    overheated starting air pipe to the cylinder head


    正确答案： B
    解析： 暂无解析

  • 第22题：

    单选题
    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


    正确答案： B
    解析： 暂无解析

  • 第23题：

    单选题
    A two-stroke diesel engine exhaust temperature will be lower than a four-stroke diesel engine of the same displacement because the （） (1) scavenging air is cooling the exhaust gases (2) exhaust cycle time is longer
    A

    (1) only

    B

    (2) only

    C

    both (1) and (2)

    D

    neither (1) nor (2)


    正确答案： D
    解析： 暂无解析

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