轮机英语新题库.doc

2270、_____ 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. A. The medium speed 4-stroke trunk piston engine B. The low speed 2-stroke crosshead engine C. The medium speed 2-stroke crosshead engine D. The low speed 4-stroke trunk piston engine 2271、_____ allows the engine to be placed wherever is most suitable, as they no longer have to be aligned with reduction gearing and shafting as is the case with conventional installations. A. Diesel engine propulsion B. Diesel electric propulsion C. Steam engine propulsion D. Gas turbine propulsion 2272、Medium speed engines have a _____ power to weight ratio than the slow speed two strokes, but due to the higher speeds tend to have _____ maintenance intervals. A. higher/reduced B. higher/increased C. lower/reduced D. lower/increased 2、The purpose of the skirt or trunk in four-stroke cycle engines is to act in a similar manner to a _____. A. crosshead B. crown C. piston rod D. connecting rod 22、The four-stroke cycle is so called because it takes _____ to complete the processes needed to convert the energy in the fuel into work. A. two strokes of the piston B. four strokes of the piston C. one revolution of the crankshaft D. four revolutions of the crankshaft 2275、In the suction stroke, the crankshaft is rotating clockwise and the piston is moving _____ the cylinder. The inlet valve is _____ and a fresh charge of air is being drawn or pushed into the cylinder by the turbocharger. A. up/opened B. down/open C. up/closed D. down/closed 2276、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. A. the suction stroke B. the compression stroke C. the expansion stroke D. the exhaust stroke 2277、Pressurized air enters the cylinder via the inlet ports and pushes the remaining exhaust gas from the cylinder in a process known as “_____”. 49617:新题:25 A. ch