单选题During the suction stroke, the piston is moving （）.AinwardsBoutwardsCdownwardsDupwards
单选题
During the suction stroke, the piston is moving （）.
A
inwards
B
outwards
C
downwards
D
upwards
参考解析
解析：
暂无解析
相关考题：
(piston area)×(piston stroke)×(numbers of the cylinders)=engine( ).A.brake horsepowerB.displacementC.cylinder volumeD.cylinder clearance
单选题In a single acting, four-stroke/cycle diesel engine, the power impulse in an individual cylinder occurs （）Aonce every crankshaft revolutionBonce every two crankshaft revolutionsConce every piston strokeDtwice every piston stroke
单选题The four strokes are called suction, compression, expansion and exhaust, but only （） stroke provides the power to drive the ship.AsuctionBcompressionCexpansionDexhaust
单选题Cross scavenging requires the fitting of （） to prevent air or exhaust gas escape when the piston is at the top of the stroke.Aa exhaust valveBa piston skirtCa piston crownDan air suction valve
单选题（） can be found on most medium to large merchant vessels even if the main engine is either a steam turbine or 2-stroke crosshead engine.AThe medium speed 4-stroke trunk piston engineBThe low speed 2-stroke crosshead engineCThe medium speed 2-stroke crosshead engineDThe low speed 4-stroke trunk piston engine
单选题The two-stroke cycle begins with the piston coming up from the bottom of its stroke, with scavenge ports in the sides of the cylinder being （）.AshutBclosingCopenedDclosed
单选题(Piston area)X(Piston stroke)K(numbers of the cylinders)=engine（）Abrake horsepowerBdisplacementCcylinder volumeDcylinder clearance
单选题Because the top of the connecting rod swings about the pin and changes direction each time the piston reaches mid-stroke, the relative speed between bearing and pin at mid-stroke is zero, （）to a maximum as the piston approaches top or bottom dead center and then （） back to zero again as the piston approaches mid-stroke and the connecting rod changes direction.Aaccelerates；deceleratesBaccelerates；acceleratesCdecelerates；deceleratesDdecelerates；accelerates
单选题When inspecting piston rings through the ports of a two-stroke/cycle diesel engine, black areas on the sealing surfaces are the result of （）Ainsufficient lubricationBimproper piston coolingCblow-byDoverload operation
单选题In the suction stroke, the crankshaft is rotating clockwise and the piston is moving （） the cylinderThe inlet valve is （） and a fresh charge of air is being drawn or pushed into the cylinder by the turbocharger.Aup；openedBdown；openCup；closedDdown；closed
单选题The piston moving up and down keeps the crankshaft （）.Ato revolveBrevolvedCrevolvingDto be revolved
单选题In comparing engines of equal horsepower, higher exhaust gas temperatures occur in a/an（）Aopposed-piston engineBdouble-acting engineCtwo-stroke/cycle engineDfour-stroke/cycle engine
单选题Scavenging in a four-stroke/cycle diesel engine occurs during the （）.Alast part of the exhaust stroke, and the first part of the intake strokeBlast part of the intake stroke onlyCearly part of the injection stroke onlyDearly part of the power stroke
单选题In diesel engines, the four basic events (intake, compression, power and exhaust) are performed once in （）.Atwo crankshaft revolutions in a two-stroke/cycle engineBtwo power strokes in a two-stroke/cycle engineCone power stroke in a two-stroke/cycle engineDtwo piston strokes in a two-stroke/cycle engine
单选题A disadvantage of a four-stroke/cycle diesel engine is （）Ahigher working temperature of piston and cylinderBthe use of scavenge portsCfewer power strokes per revolution of the crankshaftDpart of the fuel is burned as the piston is moving away from top dead center
单选题The cylinder oil is pumped into the cylinder (via non-return valves) when the piston rings pass the lubricating orifices during （）Athe upward strokeBthe downward strokeCthe power strokeDthe suction stroke
单选题Which of the following statements is true regarding the installation of piston rings on two-stroke/cycle, diesel engines as compared to four-stroke/cycle, diesel engines?（）AIn a two-stroke/cycle engine, the rings run hotter, requiring the end gap to be greaterBSome provision must be made in a two-stroke/cycle engine to keep the rings from binding in the portsCNo gap is required to exist between the ends of the ring when cold in a two-stroke/cycle engine, but a small gap is required in a four-stoke/cycle engineDThe gaps should be staggered on either side of a piston in a two-stroke/cycle engine, while staggering is not necessary in a four-stroke/cycle engine
单选题During the power stroke of a four-stroke/cycle diesel engine, most of the side thrust of a trunk-type piston is absorbed by the（）Apiston skirtBpinionCcrossheadDcompression rings
单选题It is during （） that work energy is being put into the engine; during the other 3 strokes of the piston, the engine is having to do the work.Athe suction strokeBthe compression strokeCthe expansion strokeDthe exhaust stroke
单选题During which of the listed piston stroke of a four-stroke/cycle diesel engine, is the piston moving downward?（）AIntake strokeBCompression strokeCExhaust strokeDPumping stroke
单选题One of the differences between a two-stroke engine and a four-stroke engine is,（）Aa two-stroke engine works without exhaust operationBa two-stroke engine works without compression strokeCa two-stroke engine works without expansion strokeDa two-stroke engine works without suction operation
单选题In the suction stroke air is induced into the cylinder （）In the compression stroke the air is compressed.Aby an fuel valveBthrough an inlet valveCwith an exhaust valveDfrom an outlet valve
单选题Four strokes consist of suction, compression, （） and exhaust stroke.AcombustionBcondensationCchargingDevaporation
单选题The energy for pushing this piston up can be supplied from （）, so that the piston can keep moving up and down.Athe same pistonBthe piston nearbyCthe other pistonsDthe generators on board
单选题The average pressure exerted on piston during each power stroke is termed（）Aindicated horsepowerBmean effective pressureCexhaust back pressureDcompression pressure
单选题A piston in a four-stroke/cycle diesel engine makes four strokes during each （）.Acrankshaft revolutionBmechanical cycle of operationCperiod of two combustion cyclesDcycle of two events