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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

题目

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

相似考题

1.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

2.If the diesel engine fuel injection timing is changed to delay the start of injection until the pistons are at top dead center, the engine will_________.A.backfire through the air intakesB.develop less power under loadC.have high firing pressuresD.lift its cylinder relief valves

3.Diesel engine blow-by is the leakage of combustion gases past the( ).A.oil rings onlyB.compression and scraper ringsC.cylinder liner sealingD.cylinder liner ring grooves

4.Which of the following statements represents the function of the compression rings installed at the top of a diesel Engine piston?A.Control the amount of lube oil burned in the combustion chamberB.Transmit heat from the piston to the cylinder linerC.Prevent damage to ring groove inserts by acting as a heat damD.Dissipate combustion chamber gas pressure by channeling it through the ring gap

更多“How does combustion air enter the cylinder of a two－cycle diesel engine ? Through _______. ”相关问题

  • 第1题：

    第一组： The Wartsila 50DF operates on the lean-bum principle: the mixture of air and gas in the cylinder has more air than is needed for complete combustion. Lean combustion reduces peak temperatures and therefore NOx emissions. Efficiency is increased and higher output is reached while avoiding knocking. Combustion of the lean air-fuel mixture is initiated by injecting a small amount of LFO (pilot fuel) into the cylinder. The pilot fuel is ignited in a conventional diesel process, providing a high-energy ignition source for the main engine. To obtain the best efficiency and lowest emissions, every cylinder is individually controlled to ensure operation at the correct air-fuel ratio and with the correct amount and timing of pilot fuel rejection. Wartsila has developed a special electronic control system to cope with the demanding task of controlling the combustion in each cylinder, and to ensure optimal performance in terms of efficiency and emissions under all conditions by keeping each cylinder within the operating window. Stable and well-controlled combustion also contributes to less mechanical and thermal load on the engine components. Current stringent emission regulations demand the reduction of NOx emissions. In an internal combustion engine this means controlling peak temperature and residence time, which are the main parameters governing NOx formations. In the Wartsila 50DF engine, the air-fuel ratio is very high (typically 2.2). Since the same specific heat quantity released by combustion is used to heat up a larger mass of air, the maximum temperature and consequently NOx formation are lower. The mixture is uniform. throughout the cylinder since the fuel and air are premixed before introduction into the cylinders, which helps to avoid local NOx formation points within the cylinder. Benefiting from this unique feature, NOx emissions from the Wartsila 50DF are extremely and comply with the most stringent existing legislation.

    What is the combustion feature of the Wartsila 50DF?

    A.Lean air in the cylinder

    B.Excessive fuel in the cylinder

    C.Excessive air in the cylinder

    D.Spark ignition


    正确答案：C

  • 第2题：

    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


    正确答案： C
    解析： 暂无解析

  • 第3题：

    单选题
    Which of the following statements represents the function of the compression rings installed at the top of a diesel Engine piston?（）
    A

    Control the amount of lube oil burned in the combustion chamber

    B

    Transmit heat from the piston to the cylinder liner

    C

    Prevent damage to ring groove inserts by acting as a heat dam

    D

    Dissipate combustion chamber gas pressure by channeling it through the ring gap


    正确答案： D
    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
    If the diesel engine fuel injection timing is changed to delay the start of injection until the pistons are at top dead center, the engine will（）
    A

    backfire through the air intakes

    B

    develop less power under load

    C

    have high firing pressures

    D

    lift its cylinder relief valves


    正确答案： D
    解析： 暂无解析

  • 第6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7题：

    单选题
    The longer the ignition delay period occurs in a diesel engine, the （）.
    A

    less fuel will enter the cylinder

    B

    lower will be cylinder compression temperatures

    C

    more complete will be fuel combustion

    D

    more rapid will be the rise in combustion pressure


    正确答案： B
    解析： 暂无解析

  • 第8题：

    单选题
    Fuel is admitted to a diesel engine cylinder through the （）.
    A

    intake valves

    B

    carburetor

    C

    exhaust ports

    D

    injector nozzles


    正确答案： D
    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
    Fuel droplets injected into a diesel engine cylinder must have adequate penetration to （）
    A

    prolong the ignition delay period

    B

    ensure the beginning of fuel injection

    C

    thoroughly utilize the air charge

    D

    allow controlled fuel combustion


    正确答案： D
    解析： 暂无解析

  • 第11题：

    单选题
    Diesel engines obtain combustion air through turbo chargers，blowers，or（）.
    A

    air starters

    B

    carburetors

    C

    natural aspiration

    D

    air receivers


    正确答案： D
    解析： 暂无解析

  • 第12题：

    单选题
    Proper dispersion of fuel in a diesel engine cylinder is dependent upon the （）
    A

    injection pressure

    B

    shape of combustion space

    C

    turbulence in combustion space

    D

    all of the above


    正确答案： A
    解析： 暂无解析

  • 第13题：

    Diesel engines obtain combustion air through turbo chargers，blowers，or ______．

    A.Air starters

    B.Carburetors

    C.Natural aspiration

    D.Air receivers


    正确答案：C

  • 第14题：

    单选题
    Poor combustion in a diesel engine can be caused by （）.
    A

    high compression pressure

    B

    low intake air temperature

    C

    low exhaust pressure

    D

    high scavenge air temperature


    正确答案： D
    解析： 暂无解析

  • 第15题：

    单选题
    The most serious effect of air trapped in a diesel engine jacket water cooling system is that it（）.
    A

    causes colloid suspension in the cooling water

    B

    reduces the capability of the lubrication system

    C

    can form pockets which block the flow of coolant through the system

    D

    leads to the scuffing of cylinder walls


    正确答案： A
    解析： 暂无解析

  • 第16题：

    单选题
    The diesel engine is a type of internal combustion engine which ignites the fuel by injecting it into hot, high pressure air in a （）.
    A

    air bottle

    B

    air compressor

    C

    crank case

    D

    combustion chamber


    正确答案： D
    解析： 暂无解析

  • 第17题：

    单选题
    As for a diesel engine, lack of combustion air may be due to （）.
    A

    fouling turbine

    B

    fuel pump faults

    C

    lubrication failure

    D

    excessive cooling


    正确答案： B
    解析： 暂无解析

  • 第18题：

    单选题
    Combustion gases formed in the cylinder of a diesel engine are prevented from blowing past the piston by （）
    A

    cylinder valves

    B

    compression rings

    C

    piston skirts

    D

    oil rings


    正确答案： A
    解析： 暂无解析

  • 第19题：

    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 pumps

    B

    starting air pressure too low

    C

    stop valve in air line closed

    D

    the turning gear still engaged


    正确答案： C
    解析： 暂无解析

  • 第20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 stroke

    B

    Maximum combustion pressure is reached before TDC

    C

    Turbulence in the cylinder causes a delay in ignition

    D

    Maximum cylinder firing pressure is not developed until the piston passes TDC


    正确答案： A
    解析： 暂无解析

  • 第21题：

    单选题
    The function of diesel engine piston compression rings is to （）.
    A

    prevent piston side thrust

    B

    prevent engine friction losses

    C

    transmit heat from the piston to the cylinder liner

    D

    remove oil from the cylinder combustion space


    正确答案： B
    解析： 暂无解析

  • 第22题：

    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 temperatures

    B

    low temperatures

    C

    wet

    D

    dirty


    正确答案： C
    解析： 暂无解析

  • 第23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

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