轮机英语三管轮试题--空调.doc

轮机英语
1530. Keep compartment_____ as the gas given off can be dangerous.
A. well ventilated B. well clean C. in good order D. more room
1531. The cooler as the liquid becomes, _____.
A. the faster it will evaporate B. the slower it will condense
C. the slower it will evaporate D. the faster it will flow
1532. The heat used to change a liquid to a vapor is called_____.
A. latent heat of fusion B. latent heat of vaporization
C. specific heat of vaporization D. latent heat of the gas
1533. The temperature _____ a liquid changes its state from liquid to gas depends
upon the liquid itself and upon the pressure _____ it is subjected in the containing
vessel.
A. at which/to which B. from which/at which
C. to which/from which D. in which/on which
1534. Air conditioning is the process of treating air to control _____ its temperature,

humidity, cleanliness and distribution to meet the comfort requirements of the
occupants of the conditioned space.
A. instantaneous B. instantaneously C. simultaneous D. simultaneously
1535. One of the functions of ventilation is to_____ the humidity of spaces
containing sources of moisture, or to_____ the temperature of spaces not
mechanically cooled such as the engine room.
A. increase/reduce B. reduce/increase C. increase/increase D. reduce/reduce
1536. _____ is the control of temperature and humidity in a space together with the
circulation, filtering and refreshing of the air.
A. Refrigeration B. Air conditioning C. Ventilation D. Heating
1537. _____ is the circulation and refreshing of the air in a space without necessarily
a change of temperature.
A. Refrigeration B. Air conditioning C. Ventilation D. Heating
1538. _____ is used for sensing the temperature of the room in the air condition system.
A. An expansion valve B. An evaporator C. A thermostat D. A condenser
1539. Water evaporates or steam condenses at the saturation temperature, which
depends upon the pressure, the higher the pressure _____ the saturation temperature.
A. the more B. the higher C. the lower D. the highest
1540. The shutter of the evaporator was blocked with_____, it means there was too much evaporation.
A. ice B. wooden board C. iron plate D. cotton waste
1541. The quantity of cooled air delivered by an air conditioning unit should_____
the sum of the quantity of air re-circulated to the unit and the quantity mechanically
exhausted.
A. balance B. not balance C. be more than D. be less than
1542. In the process of_____, liquid changes into gas.
A. evaporation B. frosting C. condensing D. compressing
1543. In extreme weather conditions, either hot or cold, control of the air
conditioning plant presents_____ difficulties.
A. few B. little C. a little D. less
1544. Most air conditioning units have_____ for adjusting the ratio of recirculated
fresh air. Care must be taken not to reduce the fresh air so that stuffiness or smells
arise.
A. catch plates B. dampers C. regulating valves D. fans
1545. For the intermediate condition, thermostats must be correctly set _____.
A. by trial and error B. by and large C. automatically D. very easily
1546. The process of removing moisture from air is known as _____.
A. humidification B. dehumidification C. vaporization D. evaporation
1547. If air at 95oC dry bulb temperature and 50% relative humidity is conditioned
to 75oC dry bulb temperature and 50% relative humidity, it is an example of _____.
A. cooling only B. cooling and humidifying C. cooling and dehumidifying D. adiabatic cooling
1548. Increasing the moisture content of conditioned air is known as_____.
A. moisturizing B. dehumidification C. dampening D. humidification
1549. The sum of the sensible heat and the latent heat of any substance is known as_____.
A. total heat B. residual heat C. specific heat D. superheat
1550. The heat identified by only a change in temperature is known as_____.
A. sensible heat B. latent heat C. total heat D. residual heat
1551. In reference to air conditioning, when air attains the maximum amount of
moisture it can hold at a specific temperature, it is said to be_____.
A. superheated B. saturated C. condensed D. convected
1552. Which of the following factors will have the greatest effect on the heating load
within a conditioned space?
A. Solar gain. B. Infiltration and ventilation air.
C. Occupants inside the space. D. Entertainment equipment within the space.
1553. The dew point of air is reached when the wet bulb temperature is_____.
A. Twice the dry bulb temperature B. 10oC above the dry bulb temperature
C. 5oC above the dry bulb temperature D. Equal to the dry bulb temperature
1554. The temperature at which water vapor in the atmosphere begins to condense is
called the_____.
A. dew point temperature B. condensation temperature
C. psychometric temperature D. absolute humidity temperature
1555. The heat required to change a substance from a solid to a liquid while at its
freezingtemperature, is known as the latent heat of _____.
A. fusion B. vaporization C. condensation D. sublimation
1556. The heat required to change a substance from a liquid to a gas without
experiencing a temperature change is defined as the latent heat of _____.
A. fusion B. vaporization C. sublimation D. condensation
1557. The amount of moisture in a given sample of air, when compared with the
amount of moisture the air could hold if totally saturated at the existing temperature
of the sample, is called _____.
A. absolute humidity B. specific humidity
C. effective humidity D. relative humidity
1558. The ratio of the weight of moisture contained in a given volume of air, to the
weight of moisture that the same sample would hold if saturated, is called the
_______.
A. absolute humidity B. relative humidity
C. specific humidity D. total humidity
1559. The sensible heat of air is dependent upon the _____.
A. dry bulb temperature B. wet bulb temperature
C. saturation temperature D. water vapor superheat
1560. Sludge may form in the crankcase of an air conditioning compressor as a result of _____.
A. bubbling refrigerant B. overheating and oxidation
C. lowered operating temperatures D. reducing the cloud or flash point
1561. Due to the large amount of heat picked up by the air in boiler and engine
rooms, it would be _____ to maintain ambient conditions within the comfort zone by
air conditioning .
A. possible B. necessary C. practicable D. impracticable
1562. The process of adding moisture to air to increase the relative humidity is known as ________.
A. sublimation B. humidification
C. desiccation D. moisturization
1563. The main distribution duct in an air conditioning system which contains the cooling coils and filters is called the ____________.
A. manifold B. condenser C. chamber D. plenum
1564. The humidity of the atmosphere can be determined by the use of the ______________.
A. anemometer B. Manometer C. potentiometer D. psychrometer
1565. Which of the following functions is not one of the functions of air conditioner?
A. refreshing the air B. making person upset
C. adjusting the air humidity D. adjusting the air temperature
1566. When comparing the air with 50%of relative humidity with air with 100% of
relative humidity, which one will hold more water?
A the former B the latter C not for sure D same each other
1567. For the proper control of the air temperature in an air conditioning using
chilled water circulation, which of the listed conditions should remain constant
regardless of load changes?
A. Chilled water system supply temperature
B. Chilled water system return temperature
C. Compressor discharge temperature
D. Compressor suction pressure
1568. The ___only allows for adjustment of temperature in each room by the
occupant manually controlling the air volume admitted.
A. central air conditioning system B. high velocity system
C. low velocity system D. single duct system
1569. With ducted air conditioning systems, the modern tendency is to use ___
A. central air conditioning system B. high velocity system
C. low velocity system D. single duct system
1570. Which one is not the component of a typical marine pattern self-contained unit?
A. a water cooler condenser B. a direct expansion cooler
C. a hermetic compressor D. a centrifugal pump
1571. ____ is used in typical marine pattern self-contained unit.
A. a water cooler condenser B. a slop tank
C. a expansion tank D. a centrifugal pump
1572. Under normal conditions, the quantity of air circulation becomes less and less.
What is the reason?
A. dirty delivery ducts B. too much refrigerant
C. the fouling filters D. high temperature outside
1573. Under tropical conditions, control valves have fully opened, but the room still
hot. What measures can be taken in such a case.
A. Keep the plant running all time
B. Stare another blower
C. Increase the ratio circulated to fresh air
D. Reduce the seawater flow to the condenser
1574. If a film insulation becomes damaged in air conditioning system, ___ may
from within the film.
A. evaporation B. condensation C. liquefies D. vaporization
1575. The humidifier’s valve of air-conditioner should be ___, when the temperature
is 5~8℃ in the winter.
A. decreased B. increased C. fixed D. closed
1576.The humidifier’s valve of air-conditioner should be _____, when the
temperature is lower than 0o C.
A. decreased B. increased C. fixed D. closed
1577. The air-conditioner is running in the winter and to be stopped, we should _____.
A. close Fan and Humidifier at the same time.
B. firstly close Fan and then close humidifier immediately.
C. firstly close humidifier and then close Fan immediately.
D. firstly close humidifier and then close Fan after 30 seconds.
1578. When starting air-conditioner in the winter, we should open ____ in sequence.
I. valve of warming Ⅱ. valve of humidifier Ⅲ. Fan
A. Ⅲ、Ⅱ、Ⅰ B. Ⅲ、Ⅰ、Ⅱ C. Ⅰ、Ⅲ、Ⅱ D.Ⅱ、Ⅲ、Ⅰ
1579 When air is at its dew point it is at its __________.
A. lowest absolute humidity B. lowest relative humidity
C. highest absolute humidity D. highest relative humidity
1580. Which of the fluids listed is normally used to condense the primary refrigerant in a shipboard central air conditioning system?
A. air or nitrogen B. seawater or fresh water
C. sodium nitrate brine D. calcium sulfate brine
1581. A re-heater, as used in an air conditioning system, is designed to control the ___________.
A. chilled water temperature B. dew point temperature
C. primary air temperature D. dry bulb temperature
1582. To prevent the unnecessary loading of an air conditioning system while maintaining the designed dry bulb temperature and relative humidity in an air conditioning system, you should ___________.
A. admit only enough fresh outside air to provide proper ventilation
B. reduce the air reheating system load
C. lower the compressor heat pressure
D. operate the purge recovery unit continuously
1583. A lower thermostatic temperature setting will provide a desired degree of comfort in a room where ______________.
A. low relative humidity is maintained
B. triple banded squirrel cage fans are used
C. air circulation is a maximum
D. high relative humidity is maintained
1584. In an air conditioning system, moisture is removed from the air by ___________.
A. filters B. separators C. ducted traps D. dehumidifiers
1585. Routine maintenance on a Central Control Room hermetically sealed air conditioning unit should include ________.
A. changing the air filter B. recharging the system
C. changing compressor lubricant D. renewing container vacuum
1586. In order to achieve greater dehumidification with an air conditioning system, you should __________.
Ⅰreduce the cooling coil; Ⅱ temperature increase the re-heater temperature
A.Ⅰonly B.Ⅱonly C. bothⅠandⅡ D. neitherⅠnorⅡ
1587. Which of the processes listed would be the most satisfactory method to use to lower the humidity of the air being circulated by an air conditioning system?
A. Cooling the air to a temperature just above dew point.
B. Heating the air to a point at which moisture will boil off, then re-cooling it.
C. Cooling the air to a point below dew point, then re-cooling it.
D. Heating the air and then cooling it to a point below dew point.
1588. Which of the following methods is normally used to control the temperature of air distributed from individual cooling coils in an air conditioning system using a chilled water circulation system?
A. A room thermostat activates an electric heater at each individual chilled air outlet when necessary.
B. Varying the number of passes the air makes across the coils.
C. Varying the temperature of the water through the coils.
D. Varying the quantity of water flowing through the coils.
1589. Sludge may from in the lubricating oil crankcase of a reciprocating air conditioning compressor as a result of ________.
A. wax precipitation in the lube oil
B. contamination by dust, scale, or moisture
C. refrigerant bubbles in the lube oil
D. refrigerant reducing the lube oil viscosity
1590. The compressor in an air-cooled condensing refrigeration system is short cycling on the high pressure cutout switch, ___
A. system is overcharged with refrigerant B. system is low on refrigerant
C. discharge valves are leaking excessively D. discharge valves are leaking slightly.