The main factor which determines the output of each cylinder is _____.A.the cylinder weightB.the cylinder boreC.the cylinder lengthD.the cylinder cover
The main factor which determines the output of each cylinder is _____.
A.the cylinder weight
B.the cylinder bore
C.the cylinder length
D.the cylinder cover
相关考题：
Each cylinder is closed at the top by a _____, made of a special heat-resistant steel.A.cylinder linerB.coupling flangeC.cylinder coverD.piston crown
The space between cylinder liner and jacket is called _____.A.the cooling waterB.the circulating waterC.the coolerD.the cooling water space
Because the timing of injection is crucial, _____ mounted on the camshaft, which is driven by the crankshaft are used to operate the fuel pumps, one of which is provided for each cylinder.A.gearsB.ramsC.barrelsD.cams
Which factor determines the ring dam size for a fuel oil, tubular bowl type, centrifugal purifier?A.The viscosity of the fuel.B.The quantity of water to be removed from the fuel.C.The specific gravity of the fuel.D.The quantity of dirt to be removed from the fuel.
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 cylinderB.Excessive fuel in the cylinderC.Excessive air in the cylinderD.Spark ignition
If the flame from combustion in the cylinder of a four-stroke engine past the piston into the space below, the accumulation of flammable mixture would be ignited, thus resulting in _____.A.the crankcase explosionB.lifting of the cylinder safety valveC.a scavenge fireD.opening of the manhole
The cylinder oil is pumped into the cylinder (via non-return valves) when the piston rings pass the lubricating orifices, during ______.A.the upward strokeB.the downward strokeC.the power strokeD.the suction stroke
单选题The rate of cylinder lubricating oil metered to each cylinder of a large low-speed main propulsion diesel engine is （）Athe same, whether at sea, or during maneuveringBadjusted during each hour of operation while at constant RPMChigher at sea than while maneuveringDlower at sea than while maneuvering
单选题Which of the listed problems would be indicated by an accumulation of water in one cylinder, in addition to the crankcase of an idle diesel engine?（）AExcessive cylinder linerBwater in the fuel systemCCracked cylinder linerDLeaking lube oil cooler
单选题In addition to lubricating, cylinder oil assists in forming a gas seal and contains （） which clean the cylinder liner.AadditivesBwaterCgreaseDacid solution
单选题The bore of each cylinder is formed in a liner which can be （） when worn out.AweldedBreplacedCdrilled againDbored
单选题A practical way of checking for excessive fuel injection in one cylinder of an operating diesel engine is to （）Afeel the high pressure fuel lineBcheck the cylinder exhausts for white smoke frequentlyCcheck the cylinder exhaust temperatureDisolate each cylinder and inspect the injector
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 （）Acheck the cylinder exhausts for black smokeBlisten for combustion knock in that cylinderCisolate each cylinder and inspect the injectorDcheck the cylinder exhaust temperature frequently
单选题For Vee-form engines, （） is shaped to given two slopping surface on which （） are placed at the correct relative angle to each other.Athe bottom of the column；the cylinder blocksBthe top of the column；the cylinder headsCthe top of the column；the cylinder blocksDthe bottom of the column；the cylinder heads
单选题The main factor determining the output of each cylinder is the cylinder （）.AdensityBboreCweightDmaterial
单选题The amount of fuel delivered for each cycle must be in accordance with the engine load, and the same quantity of fuel must be delivered to each cylinder for each power stroke at that load.Which of the following statements describes this requirement?（）AProper timingBAccurate meteringCSuitable injection rateDSuitable atomization rate
单选题On the top of the cylinder is mounted the cylinder cover which is pressed onto （） of the cylinder liner by means of nuts and studs.Athe camshaftBthe flangeCthe ridgeDthe bulge
单选题There is an injection pump for each cylinder, which is usually operated once every cycle by （） on the camshaft.Aa gearBa camCa rodDa miler
单选题A-frames are mounted on the bed plate and support （） and cylinder block.Athe main bearingBthe cylinder coverCthe entablatureDthe sump
单选题Which of the fuel injection systems listed uses a spring loaded differential spray needle valve and individual pump for each cylinder?（）ACommon-rail injectionBAir injectionCJerk pump injectionDDistribution injection
单选题The cylinder covers and the liners are bolted together by means of （）.Abolts welded into the cylinder headBbolts welded into the cylinder framesCstuds screwed into the cylinder headDstuds screwed into the cylinder frames
单选题The air distributor is conventionally driven by（） and distributes into each cylinder by（） certain sequence.Acamshaft；fresh airBcamshaft；starting airCelectronic motor which is controlled by a computer；fresh airDelectronic motor which is controlled by a computer；starting air
单选题Each cylinder in a two stroke cycle engine experiences combustion（）.Aonce each crankshaft revolutionBtwice each crankshaft revolutionCevery other crankshaft revolutionDevery fourth stroke
单选题Cylinder lubrication oil for low speed main propulsion diesel engines is admitted to each cylinder during （）.Athe power strokeBthe compression strokeClow load operation onlyDperiods of standby
单选题The main factor which determines the output of each cylinder is （）Athe cylinder weightBthe cylinder boreCthe cylinder lengthDthe cylinder cover
单选题In the （） pressure charging system the pulse of energy that occur as the exhaust is released from the cylinder to improve the output of the turbocharger.AconstantBpulseChighDnone of the above