轮机英语新教材练习题315题

1、轮机英语新教材练习题1.when a ship in loaded condition floats at arbitrary water line,its displacement is_to the relevant mass of water displaced by the ship. a equal b larger c smaller d equivalent2.the displacement of a ship is_to the total weight,all told,of the relevant loaded ship. a larger b equal c smal

2、ler d equivalent3.which one is not true? a two main areas of skill are involved in the construction of ship. b there are distinct divisions in responsibilities between naval architects and marine engineers. c each ship will assume varying proportions according to its type. d ship can be divided into

3、 different categories from different perspectives.4.why a gearbox is needed in a ship driven by a medium-speed diesel engine? a to reduce the main engine speed. b to increase the main engine speed. c to govern the main engine speed. d to fix the propeller shaft.5.a propeller,in order to operate effc

4、iently,must rotate at a relatively_speed. a high b low c fast d lowly6.in a diesel engine,_offers the heat energy directly;_works as working medium and changes the heat energy to mechanical energy. a the burning of the fuel/medium shaft b fuel spray/fresh air c fuel/fuel spray d the burning of the f

5、uel/the burned gas mixture7.in a diesel engine,_works as working medium and changes the heat energy to mechanical energy,_changes the reciprocating movement to rotary moment. a fuel spray/the burning of the fuel b the burned gas mixture/connecting rod c medium shaft/crankshaft d the burned gas mixtu

6、re/piston rod8.one of the differences between a two-stroke engine and a four-stroke engine is ,_ a a two-stroke engine works without exhaust operation b a two-stroke engine works without compression stroke c a two-stroke engine works without expansion stroke d a two-stroke engine works without sucti

7、on operation9. one of the differences between a two-stroke engine and a four-stroke engine is ,_ a a two-stroke engine cant work without cylinders b a two-stroke engine cant work without pistons c a two-stroke engine cant work without crankshafts d a two-stroke engine cant work without a blower10.in

8、 a diesel engine,when the fuel is injected into the cylinder_ a the piston is just coming upward from the bottom dead center. b the piston has moved about one-fifth of the way up. c the piston has moved most of the way up and almost reached the tdc d the piston has just past the tdc11._is the main r

9、eason that reduces the power advantage of a two-stroke engine over a same size four-stroke to about_. a inefficient scavenging/twice b inefficient scavenging/1.8 times c fewer strokes in a circle/twice d fewer strokes in a circle/1.8 times12.if the engine is naturally aspirated,or is a small highspe

10、ed type with a centrifugal turbocharger,the period of valve overlap,i.e.when both valves are_,will be_,and the exhaust valve will close some 10_top dead canter. a open/short/after b closed/short/after c open/long/before d closed/long/before13.in a two-stroke engine,there are always a series of openi

11、ngs known as_,and in some circumstances,there are also openings known as_,in the part of the cylinder liner inside the scavenging air box. a scavenging air ports/exharst ports b inlet ports/scavenging air ports c scavenging air ports/inlet ports d exhaust ports/inlet ports14.in some type of twostrok

12、e engines,besides some small holes for_,starting valve,safety valve,indicator cock,and so on,there is a large central opening in each cylinder cover for mounting the_ a fuel valves/exhaust valve b exhaust valves/inlet valve c fuel valves/inlet valve d exhaust valves/fuel valve15.in a twostroke ,the

13、piston consists of a lower part,which is named as_and usually made of_,and a upper part,which is referred to as_and made of_ a lowhalf/cast iron/tophalf/heatresistant steel b lowhalf/aluminum/tophalf/stainless steel c piston skirt/cast iron/piston crown/heatresistant steel d piiston skirt/aluminum/p

14、iston crown/stainless steel16.in order to keep the oil film on the cylinder liner during the running-in period,the piston ring are slightly rounded_ a on both the external and internal top edges b on both the external top and bottom edges c on both the external and internal bottom edges d on all the

15、 four edges17.in order to control thermal stresses,some types of modern engines use pistons with_ a heavy wall and intensive cooling b heavy wall and no cooling c thin wall and no cooling d thin wall and intensive cooling18.in order to improve the working conditions of the crosshead bearings,the bea

16、ring pressure is made_and the peripheral speed is made_in later designs. a smaller/higher b higher/smaller c smaller/smaller d higher/higher19.when the heavy fuel oil is heated to achieve the viscosity of 1015 cst,_may occur,to avoid this ,a _system is used in most occasions. a boiling and cavitatio

17、ns/low temperature b boiling and cavitations/pressurized c leaking and boiling/low temperature d leaking and boiling/pressurized20.the fuel from the bunker tanks must be treated by_before entering the service tanks.from where the fuel enters_ a centrifugal separators/the engine cylinder b oily water

18、 separators/the engine cylinder c oily water separators/the fuel supply system d centrifuges/the fuel supply system21.a full-flow 50m filter is installed_,so the injection system components on the main engine are safeguarded. a as close to the main engine as possible b as close to the main pump as p

19、ossible c just before the fuel valve d just before the booster pump22.the booster pump,which supplies diesel oil to _,should have a possibility of being powered by compressed air or by emergency power. a the main engines b the auxiliary engines c the emergency generator engine d the auxiliary engine

20、s and the main engine(s)23._is harmful for fuel pumps,fuel valves,cylinder liner,exhaust valve seats,and the turbocharger blades as well. a bad combustion of the fuel b bad atomization of the fuel c liquid contaminants d solid contaminants24.as an alternative to the conventional seawater cooling sys

21、tem,_is based on _principles about cooler locations,flow control and preheating,but with a central cooler and one additional ste of pumps. a the central cooling system/different b the central cooling system/the same c the open cooling system/different d the open cooling system/the same25.an alarm de

22、vice inserted between the deaerating tank and the expansion tank notify the onwatching crew that_ a the expansion tank is lack of water b the expansion tank is over flowing c there is something wrong with the cooling system d there is something wrong with the engine26.the_cooling system needs least

23、maintenance work for_in this kind of system. a open/the minimum components b open/the high cooling efficiency c central/there are more coolers and a extra set of pumps d central/there is only one component contacts seawater27.about the jacket water,that of the auxiliary engines usually is circulated

24、 by_pumps,and the main engine usually_ a an enginedriven/as well b an enginedriven/has an independent pump c an independent/as well d an independent/has an enginedriven pump28.in order to maintain a constant outlet water temperature of 80-85c from the engine,a three-way valve is installed_ a at the

25、jacket cooler outlet to control the flux through the engine b at the jacket cooler outlet to control the flux through the cooler c at the engine outlet to control the flux through the engine d at the engine inlet to control the flux through the engine29.in modern installations,the main engine and th

26、e standby auxiliary engines_ a can be started at low temperature and are free from preheating b usually are preheated by steam before being started c are kept at a constant temperature and free from preheating d are kept at a low temperature to save energy30.a marine diesel engine is started by_ a s

27、upplying high pressure oil into a hydraulic motor b supplying high temperature air into the cylinder c supplying high pressure air into the cylinder d electrical igniting31.the starting air system of an engine on board usually has interlocks in order to_ a ensure a successful shutting down at emerge

28、ncy conditions b ensure a successful starting at emergency conditions c prevent the engine from starting at some abnormal conditions d prevent the engine from starting at emergency conditions32.in the starting system,the automatic valve is controlled by_,and the cylinder start valves are controlled

29、by_ a pilot air/pilot air b handle/solenoid c handle/pilot air coming through the distributor d solenoid/pilot air coming through the distributor33.the starting air entering the cylinder begins when the piston_ a has nearly come to the tdc b has just past the tdc c has nearly come to the bdc d has j

30、ust past the bdc34.when starting an engine,the compressed air enters the cylinder when the corresponding piston is in position of its_ a suction stroke b compression stroke c power stroke d exhaust stroke35.when an engine is starting and has got a sufficiently high speed ,say about 20rpm,_ a the sta

31、rting air supply is cut off and fuel is injected into the cylinders b the fuel feeding is cut off and the turning gear is put in c the starting air supply is cut off and the turning gear is taken out d the electric blower is shut down and fuel is injected into the cylinders36.the air distributor is

32、conventionally driven by_and distributes_into each cylinder by certain sequence. a camshaft/fresh air b camshaft/starting air c electronic motor which is controlled by a computer/fresh air d electronic motor which is controlled by a computer/starting air37.the following options are all the functions

33、 of lubricating oil except_ a removing heat and deposits b neutralizing acidic products c lubricating d improving combustion efficiency38._diesel engines generally have two systems of lubrication:a total loss system feeding_and a circulating system lubricating the running gear and cooling the piston

34、s. a large crosshead type/crossheads b high speed/the cylinders c large crosshead type/the cylinders d four-stroke/pistons and cylinders39.in some diesel engine designs,the injection of cylinder oil is timed to impings when the piston_and only impinge on_ a is coming upward/cylinder ring belt b is g

35、oing downward/piston ring belt c is coming upward/ piston ring belt d is going downward/ cylinder ring belt40.large crosshead type engine generally has two lubrication systems,a function performed only by cylinder oil system is_ a lubricating b cooling c sealing d cleaning41. large crosshead type en

36、gine generally has two lubrication systems,a function performed only by crankcase oil system is_ a lubricating b cooling c cleaning d neutralizing42.“the use of a poor quality oil can lead to rapid deterioration of its properties with the resultant formation of deposits in the piston crown which in

37、turn results in a considerable reduction in heat transfer with subsequent overheating and thermal cracking”.according to this sentence,we can know that the principle reason of the overheating and thermal cracking is_ a the use of a poor quality oil b the deterioration of its properties c the formati

38、on of deposits d the reduction in heat transfer ability43.gas exchange,which is a basic part of the cycle of an internal conbustion engien,is_ a the supply of normal air and removal of compressed air b the supply of fuel oil and combustion of the atomized oil c the supply of fresh air and removal of

39、 exhaust gases d the supply of fresh air and removal of extra heat 44.“this increase in charge air density is accomplished on most modern diesel engine types by use od exhaust gas turbo-charging,in which a trubine wheel driven by exhaust from the engine is rigidly coupled to a centrifugal type air c

40、ompressor”.according to this sentence,we can know that_increases charge air density,_drives the compressor directly. a a modern diesel engine/a turbine wheel b a modern diesel engine/exhaust gases c a compressor/an exhaust gas turbocharger d a compressor/a turbine wheel45.when the air charge contact

41、s with the cylinders and pistons and mixes with the residual gases,it will_ a increase in temperature b lose its energy partly c expand and do work d beging to be compressed46.usually we take the cooling effect of the air flown through the cylinder during the overlap period as_ a inevitable b harmfu

42、l c helpful d unacceptable47.in slow speed twostroke engines,the fresh air entering begins when_and stops as_ a the inlet port is opened by the up coming piston/the port is closed by the down going piston b the inlet valve is opened by the down going piston/the inlet valve is closed c the inlet port

43、 is opened by the down going piston/the port is closed by the up coming piston d the inlet valve is opened48.the_is employed to warm up a large diesel engine before its starting. a hot air b hot boiler water c cylinder water d hot seawater49.which one of the followings may not be checked before engi

44、ne starting? a tank level b various filters c drains d seawater temperature50.when the direction handle of telegraph is moved,the relative position of camshaft and crankshaft will be_ a changed accordingly b unchanged c positioned ahead d positioned astern51.which of the followings will affect the s

45、pray of fuel oil? a coke deposits b cylinder water temperature c asphalt in fuel oil d lub oil52.which one of the folloeing may contribute to the forming of coke around the nozzle of fuel valve? a too much water in fuel oil b too much asphalt in fuel oil c larger nozzle holes d more nozzle holes inl

46、et valve is closed53.the transmission system transmitting power from the engine to the propeller is composed of shafts,bearings,and_ a propeller b flying wheel c main engine d crankshaft54.the thrust from the propeller to the hull of the ship is transferred by_ a tie rod b thrust block c bedplate of

47、 main engine d frame of main engine55._is used to prevent the entry of sea water to the machinery space. a a special sealing gland b propeller c tailshaft d sterntube bearing56.oil pressure in the lubrication system is_than the static sea water head to ensure that sea water cannot enter the sterntub

48、e in the event of seal failure. a higher b lower c very higher d very lower57.the propeller consists of a_with several blades of helicoidal form attached to it. a shaft b boss c wheel d lever58.the difference between fixed pitch propeller(fpp) and controllable pitch propeller(cpp) is in that a for f

49、p,once fitted,the position of the blades can also be changed in operation b for cp, once fitted,the position of the blades can also be changed in operation c the cp type has a relatively smaller hub compared with the fp propellers d the fp type has a relatively larger hub compared with the cp propel

50、lers59.in conventional system,the injection pressure_,while its_in common rail diesel engines. a fluctuates with the engine speed to some extent/independent of the engine speed b keeps constant at all engine speed/dependent on the engine speed to some extent c keeps constant at all engine speed/inde

51、pendent of the engine speed d is decided by the engine speed/constant at all engine speed60.in common rail engines,the fuel is_before is injected into the cylinders a stored in a common fuel line b pumped by the injection pump c at low pressure d already atomized61.in a common rail engine,the fuel i

52、s injected into cylinders_ a by injection pumps b at a time decided by the injection pump timing c by a signal opening the magnetic valves d at a time decided by the cam directly62._uses one or two high pressure pumps for all the cylinders with one more standby,while_have a separate highpressure pump for each cylinder. a a common rail engine/conventional engines b a conventional engine/common rail engines