轮机英语试题上海答案.docx

1、轮机英语试题上海答案1. The reciprocating motion of the piston is converted to _motion of the crankshaft by the connecting rod ,which swivels about the wrist (piston or gudgeon )pin at the top ,and at its bottom end rotates about the crank pin .a .turning b. relative c. rolling d. back and forth 2.While these

2、are theoretical cycles that are only _in reality ,it is the dual combustion cycle that most accurately represents the operation of most diesel engines of current design . a .approximated b. closed c. approach d. accurate 3, In the Otto cycle ,a charge of fuel and air is ignited by a spark and burns

3、explosively ,so rapidly that combustion is completed before the piston begins to move down and therefore _at constant volume .a .take the place of b. occurs c, is taken place d. carry out4. Practical considerations prevent all these other factors from _,but the factor remains that the closer the dua

4、l combustion cycle can be made to approach an Otto cycle ,with a large fraction of the fuel burning rapidly before the piston commence its downward stroke ,the higher will be its theoretical thermal efficiency . a .being the same b. equal c. is equal d, equation 5.Otto and dual combustion cycles are

5、 related by the manner in which combustion takes place ,if all other factors were equal ,the theoretical thermal efficiency _higher for an Otto cycle .a .would be b. will be c .was d .is 6.In steam turbines high pressure steam is directed into _blades or vanes attached to a shaft ,causing it to rota

6、te . a .a series of b. a serious of c, series of d. serious 7.Gas turbines differ from steam turbines _gas rather than steam is used to turn a shaft . a .since(in that ) b. so that c. therefore d. thus 8. As the cylinder volume increases ,however the continued combustion maintains the pressure in th

7、e cylinder until injection and then combustion _. a .stop b. increase c. cease d .to cease 9.The exhaust stroke actually begins just before the piston reaches bottom dead center ,when the exhaust valve opens and the residual high pressure in the cylinder _the exhaust manifold as the gases blow down

8、. a .is relieved into b. is reduced into c. is discharging to d. is charged into 10. Fuel injection begins during the _stroke , before the piston reaches top dead center . a .expansion b. suction c. compression d. exhaust 11.Without exception ,modern oil-burning diesel engines achieve these _with so

9、lid injection systems . a .objectives b. gate c. door d. object 12.It is important to _that in a high speed engine the crankshaft rotates farther in a given period of time than in a low speed engine ,which explains the generally lower tolerance of high speed engines for fuel of low ignition quality

10、.a .indicate b. write c. explain d. show 13.If the pressure rises too sharply the combustion becomes audible ,a phenomenon known as _.a .diesel knock b. diesel engine c. mechanical d. fire knock 14.Once the combustion has been established in the cylinder ,further fuel droplets entering the cylinder

11、will burn as soon as they have penetrated ,heated ,vaporized ,and mixed ,so that the combustion rate _the injection rate by the preparation time . a .lags behind b. leading c. is slower than d. is the same as 15.Typically ,however ,_some irregularities reflecting combustion of incompletely burned fu

12、el or of intermediate combustion products ,and some delayed chemical end reactions . a .there will be b. there is c. there will have d. there has 16.Compressor discharge pressure is usually described by its ratio to _,called the pressure ratio . a .intake pressure b. discharge pressure c. water pres

13、sure d .exhaust pressure 17.Currently ,turbo-chargers are suitable for pressure ratios _4.0.a .as high as b. such high as c. as low as d. as well as 18. Maintaining the engine in a warm condition helps in minimizing _.a .friction b. wear c. corrosion d. rust 19. Auxiliary engine _self-contained cool

14、ing circuits .a .tends to b. tend to c. tends to have d. tend to have 20.Cylinder oil is a high viscosity mineral oil ,with a _matched to the anticipated sulfur content of the fuel . a .TAN b .TBN c. SAN d. SBN 21.In crosshead engines in good condition the cylinder oil consumption may usually be _.

15、a .below 0.1g /hp. Hr b. above 10g /hp .hr c. below 1.0g/hp d. zero 22.The change from one fuel to another _gradually to allow temperature in the system to stabilize . a .take place b. are taken place c. should take place d. should be taken place 23.Refining separates crude oil into number of hydroc

16、arbon products in a process based on their _,with the lightest products having the lowest boiling points (evaporation points ). a .boiling points b. flash points c. freezing points d. melting points .24.Far more frequently it is blended with a distilled product (the cutting stock )to produce a less

17、viscous intermediate fuel ,which ,depending on the proportions used ,can itself _light or heavy . a. be defined as b .be referred to as c. called d. name 25.It can be seen that relatively small fraction of distilled product can reduce the viscosity substantially ,so that even the lighter blends will

18、 contain _of undesirable constituents .a. large amounts b .important amounts c. small amounts d. a few 26.The presence of sulfur in the fuel therefore indicates a potential for _,i.e. ,acidic attack of surfaces exposed to the exhaust gas when they are at or below about 150。C . a. cold end corrosion

19、b. hot end corrosion c. corrosion at the end d. corrosion in the end 27.Torsional vibration arises (results)from periodically _superimposed upon the steady torque being transmitted to the load . a .changing torque b. strong torque c. very great torque d. steady torque 28. When a propulsion system is

20、 operated in it normal range of RPM ,torsional vibration becomes a problem if a source of excitation has a first or higher order frequency _one of the natural frequencies for torsional vibration of the rotating system . a .near b. closed to c. shut off d. close 29. Under these circumstances ,the tor

21、que variation of the source will force the rotating system into resonance ,causing it to oscillate torsionally at high angular amplitude ,with corresponding high stresses that could _shaft line component fatigue failure . a .result from b. lead to c. with the result that d. result in 30. In geared i

22、nstallations at low power levels ,the oscillations can cause the gear tooth loaded faces to _separate and chatter . a .irregularly b. periodical c. period d .regularly 31. _, the metal expands . a .heating b. heated c. heats d. to heat 32. In the evaporator ,the liquid vaporizes at a constant pressu

23、re and temperature as heat is _through the walls of the cooling coils . a .given up b. packed up c. put up d. picked up 33. A pump required in the hydraulic system which can immediately pump fluid in order to provide a hydraulic force that will move the rudder is of _type . a .variable delivery b. c

24、onstant delivery c. small delivery d. large delivery 34.Around the furnace are banks of tubes , which have connected with two drums _. a .respectful b. respectfully c. respectively d. respective 35. All working parts of the equipment which _wear or to damage should be easily accessible for maintenan

25、ce . a .are reliable b. are liable to c. are likely to d. are possible 36. In early applications the control station _the open type placed in the engine room . a. was of b. is of c. were d. is 36. These stored data are then available for local display and printout as well as _ashore by satellite and

26、 /or modem to company headquarters .a .transmission b. transmitted c. transferred d. transportation 37. The _of a digital central operating system and its uses are limited only by the imagination of the engineer and the desires of the owner .a .implementation b. carry out c. conduct d. achievement 3

27、8. Internal storage _the memory bank used as the residence for instruction ,computation ,and other functions that determine the _of the system . a .feature b. performance c. speed d. capacity 39. Input register units to provide a path into the internal storage for the instructions or data upon which

28、 the computer _as a system . a .does b. functions c. sails d. compares 40. Output registers providers of the path for the results of any _directed by the system to be output to the observer or the central system .a .operation b. maintenance c. components d. communications 41. It is necessary that th

29、ese machines _in synchronism with each other . a .being b. are c. were d. be 42. It may be necessary to have the windings _before putting the motor into operation .a .dried b. drying c. being dried d. having dried 43. The motor stops running , the power supply _in trouble .a .is b. been c. being d.

30、be 44. There is a danger of the starting current _that the windings are burnt out . a .to increase b. to be so increased c. increased d. being so increased 45.The propeller advances a distance through the water in one revolution equal to its pitch minus a slippage ,called slip ,which _the axial velo

31、city induced by the propeller . a .is equivalent to b. equivalent to c. is equal to d. equivalence of 46. Class I for the majority of merchant vessels gives tolerance on pitch of the blades of+_0.75percent with any local pitch on the blade _+_2percent . a .being b. is c. are d. will be 47.The endura

32、nce portion of the trial demonstrates the ability of all the ship ,s system to _for a prescribed extended period of time at maximum speed and power without the failure of the components . a .perform b. prediction c. predict d. evaluated 48. This information is useful to the ships officer in _the ship and may be required as evidence in a legal action involving the ship . a .handling b. exercising c. operation d. drive 49. Trainin