1、2020/9/14,Good good study,day day up!,1,Lesson Four Air Conditioning Systems and development trend,2020/9/14,Good good study,day day up!,2,Topics,What is air conditioning systems? And its classification,New technologies for further systems,Configuration and discussion of Central-station system,Confi

2、guration and discussion of unitary air conditioning systems,Text and key words learning,2020/9/14,Good good study,day day up!,3,air conditioning system 空氣調(diào)節(jié)系統(tǒng) humidify 加濕 dehumidify 除濕 filter 過濾 過濾器 central-station system 集中式系統(tǒng) unitary system 單元式系統(tǒng) mechanical room 機(jī)房 radiant-heat systems 輻射采暖系統(tǒng) blow

3、er 送風(fēng)機(jī) face velocity 迎面風(fēng)速 face area 迎風(fēng)面積 mixing plenum 混合箱 damper 閘板 direct expansion(DX) 直接膨脹 vibration damper 減震器 acoustic lining 隔音層 acoustic board 隔音板 grilles 格柵 register 送風(fēng)口 the fan-coil unit system 風(fēng)機(jī)盤管系統(tǒng) high-velocity conduit unit system 高速送風(fēng)系統(tǒng),Frequently used words and phrases,air conditioni

4、ng system 空氣調(diào)節(jié)系統(tǒng) humidify 加濕 dehumidify 除濕 filter 過濾 過濾器 central-station system 集中式系統(tǒng) unitary system 單元式系統(tǒng) mechanical room 機(jī)房 radiant-heat systems 輻射采暖系統(tǒng) blower 送風(fēng)機(jī) face velocity 迎面風(fēng)速 face area 迎風(fēng)面積 mixing plenum 混合箱 damper 閘板 direct expansion(DX) 直接膨脹 vibration damper 減震器 acoustic lining 隔音層 acoust

5、ic board 隔音板 grilles 格柵 register 送風(fēng)口 the fan-coil unit system 風(fēng)機(jī)盤管系統(tǒng) high-velocity conduit unit system 高速送風(fēng)系統(tǒng),2020/9/14,Good good study,day day up!,4,An air conditioning system is an assembly of various components which operate in a controlled manner to produce a specified condition of the air withi

6、n a space or building. To provide complete air conditioning a system must accomplish all the following: heat, humidify, cool, dehumidify, ventilate, filter, and circulate.,Topic one: What is air conditioning systems,2020/9/14,Good good study,day day up!,5,Configulation,Central-station,Unitary system

7、s,Cool supply,Heat supply,Functional,A central-station system is one in which the components of the system are all grouped together in one central mechanical room and the conditioned air is sent from there to the spaces to be conditioned through extensive ductwork.,These are usually installed in or

8、immediately adjacent to a zone or space to be conditioned.,Topic one: Classification of air conditioning systems,2020/9/14,Good good study,day day up!,6,Topic Three: Configuration and typical variants of Central-station system- Typical variants for design,Capacity,25 cool ton;10000cfm; 40000cfm or10

9、0coll ton,Plant 80000?,Filter &mix box,Mixing plenums/filter Vertical installation,Reuse,2020/9/14,Good good study,day day up!,7,Topic Three: Configuration and typical variants of Central-station system- Typical variants to discuss,Refrigeration and heating equipment,Air conditioning units close to

10、cooling and heating equipment, better to use direct expansion refrigerant coil and hot-water coils,Or else, the chiller water or hot water will be the medium and pumped to the air conditioning coils,Noise and vibration,Extreme importance, if located on upper floors, must make sure the stress design

11、is satisfied ,every part should be designed quiet, such as fan motors, ducts and duct turns, and so on,2020/9/14,Good good study,day day up!,8,The Air-Conditioning and Refrigeration Institute (ARI) defines a unitary air conditioner as one or more factory-made assemblies that normally include an evap

12、orator or cooling coil and a compressor and condenser combination. It may include a heating function as well. A unitary air conditioner having more than one factory-made assembly (e.g., indoor and outdoor units) is commonly called a split system.,Unitary air conditioner: 單元式空調(diào)器 Split unit: 分體式空調(diào)器,20

13、20/9/14,Good good study,day day up!,9,Topic Three: Configuration and typical variants of unitary system-Classification,1 The remote air conditioning unit system. The unit is a factory-assembled combination of equipment which will perform all seven air conditioning functions. They are separated from

14、compress chillers and heat source. The cooling coil may be either of the direct-expansion or chilled water type, and the heating coil may be either for hot water or for steam. 2 The self-contained air conditioning unit system. This type of unit incorporates the refrigeration condensing unit and the

15、heating plant (frequently a gas-fired furnace) all in the same enclosure. 3 The unitary system for multi-room buildings. These systems are actually combination unitary-central-station systems.,分離式空氣處理單元系統(tǒng),獨(dú)立式單元空調(diào)系統(tǒng),多房間建筑中的單元空調(diào)系統(tǒng),2020/9/14,Good good study,day day up!,10,Topic Three: Configuration and

16、 typical variants of unitary system-Classification,1 The fan-coil unit system. Unit conditioners of this type provide complete air conditioning using chilled water for cooling and hot water for heating. The same coil is ordinarily used for both summer and winter operation. The fan is a centrifugal t

17、ype and blows freely into the room discharging conditioned air upward and slightly outward into the room. Slow fan and low static pressure permit extremely low noise level and power requirements.,2020/9/14,Good good study,day day up!,11,Topic Three: Configuration and typical variants of unitary syst

18、em-Classification,2 The duct-type unit system. The units of this type system are commonly referred to as convectors. The convector has no fan and may not have heating or cooling coils, although some types have reheat coils as local boosters for winter operation. There is a plenum chamber in the bott

19、om of the unit which is supplied by a conventional duct from a central-station air conditioning system. Completely conditioned air enters the plenum both winter and summer. This air is called the primary air. It exits upward from the plenum through a series of nozzles, attaining a rather high veloci

20、ty as it flows upward through the venturi-shaped throat of the convector. The Bernoulli effect created produces an area of low pressure into which room air is drawn through a grille in the front of the unit.,2020/9/14,Good good study,day day up!,12,Topic Three: Configuration and typical variants of

21、unitary system-Classification,3 The high-velocity conduit unit system. The air conditioning unit of this system is again known as a convector. Primary air from a central-station air conditioning unit is supplied through small-diameter conduits at high static pressure and high velocity. The advantage

22、s of the high-velocity conduit system center around the space-saving features inherent in its design. High-velocity systems, on the other hand, can handle 30-story and higher buildings from one central mechanical room, since only one-fourth of the supply air actually comes from the central-station e

23、quipment, and it travels in the conduits at a speed four to five times that common in conventional duct systems.,2020/9/14,Good good study,day day up!,13,Air Conditioning Systems Central-station System Capacity considerations Filter and mixing plenums Refrigeration and heating equipment Always be in

24、sulated Noise and vibration Unitary Air Conditioning Systems fan-coil unit system duct-type system high-velocity conduit unit system,Topic Five: Text learning and keywords,2020/9/14,Good good study,day day up!,14,1. An air conditioning system is an assembly of various components which operate in a c

25、ontrolled manner to produce a specified condition of the air within a space or building. 2. To provide complete air conditioning a system must accomplish all the following: heat, humidify, cool, dehumidify, ventilate, filter, and circulate.,assembly: 集合 裝配 controlled manner: 控制方法 specified: 指定的,acco

26、mplish: 完成 達(dá)到 filter: 過濾 circulate:換氣,Topic Five: Text learning and keywords,2020/9/14,Good good study,day day up!,15,3. A central-station system is one in which the components of the system are all grouped together in one central mechanical room and the conditioned air is sent from there to the spa

27、ces to be conditioned through extensive ductwork.,central-station system: 集中式空調(diào)系統(tǒng) mechanical room: 機(jī)房 ductwork: 管道系統(tǒng),Topic Five: Text learning and keywords,4. Unitary systems make use of factory-assembled and tested air conditioning units. These are usually installed in or immediately adjacent to a

28、zone or space to be conditioned.,unitary system: 單元式空調(diào)系統(tǒng) immediately: 直接地 adjacent: 鄰近的 factory-assembled and tested: 廠家裝配和測試的,2020/9/14,Good good study,day day up!,16,5. Another possible classification divides air conditioning systems into cooling systems and heating systems. Cooling systems may in

29、 turn to be classified in terms of the cooling medium and cooling surface used. Heating systems are classified as warm-air systems or radiant-heat systems. 6. The term “central-station” is ordinarily not applied to systems of less than about 25 tons of cooling capacity, circulating about 10,000 cfm

30、of conditioning air.,term:術(shù)語 cfm: cubic feet per minute 立方英尺/分,cooling medium: 冷卻介質(zhì) cooling surface: 冷卻表面 warm-air system: 熱空氣采暖系統(tǒng) radiant-heat system: 輻射采暖系統(tǒng),Topic Five: Text learning and keywords,2020/9/14,Good good study,day day up!,17,7. Refrigeration condensing units and steam or hot-water boil

31、ers for these purposes may be in the same mechanical room with the air conditioner or may be in an adjoining room or in the basement. 8. It will be recalled that heat transfer between air and metal surfaces requires rather large surfaces areas.,refrigeration condensing units: 制冷機(jī) adjoining: 鄰近的 base

32、ment: 地下室,recall: 回憶引申為提醒 rather: 相當(dāng)?shù)?Topic Five: Text learning and keywords,2020/9/14,Good good study,day day up!,18,9. Heating and cooling coils handling air at face velocities of around 500 fpm must present about 2 sq ft of face area (four-row coil) for each 1,000 cfm of air handled.,face velocit

33、y: 迎面風(fēng)速 face area: 迎風(fēng)面積 four-row coil: 4排盤管 fpm: feet per minute 英尺/分鐘,Topic Five: Text learning and keywords,10. If the job requires more total capacity than this, two or more “zones” should be planned with an air conditioning system installed to handle each zone.,zones: 空調(diào)區(qū)域,2020/9/14,Good good st

34、udy,day day up!,19,11. Blowers are manufactured commercially in capacities up to 200,000 cfm, but the associated equipment for units handling this much air is heavy, difficult to fabricate and install, and difficult to service. 12. Supply and return ductwork and outside air intakes have to be extrem

35、ely large for units handling over 50,000 cfm, and the problem of locating these ducts in the building structure is extremely difficult.,blower: 送風(fēng)機(jī) associated: 關(guān)聯(lián)的 相關(guān)的 service: 保養(yǎng) 維護(hù),supply ductwork : 送風(fēng)管道 return ductwork: 回風(fēng)管道 extremely: 極端地 非常地,Topic Five: Text learning and keywords,2020/9/14,Good

36、 good study,day day up!,20,13. The nature of the building itself frequently determines the extent of zoning to be specified, a theatre or department-store installation, where spaces of large cubical content are the rule, may usually be most economically conditioned by only a few (perhaps only one) c

37、entral-station air conditioning units. 14. Office buildings, schools, and similar buildings with many rooms lend themselves to more zoning, with air conditioning units of 10,000 to 30,000 cfm being in common use.,department-store: 百貨公司 rule: 規(guī)律,lend itself to: 適合于,Topic Five: Text learning and keywo

38、rds,2020/9/14,Good good study,day day up!,21,15. Return air and fresh outside air should be brought into a plenum for mixing prior to being filtered.,return air: 回風(fēng) fresh outside air: 室外新風(fēng) plenum: 靜壓箱,Topic Five: Text learning and keywords,16. The damper may be controlled by a thermostat to admit le

39、ss outside air when extreme outdoor temperatures occur or by smoke and odor-sensing devices in the conditioned space in order to increase the amount of ventilation air as needed, owing to the nature of the occupancy.,damper: 閘板 smoke and odor-sensing devices: 煙或氣味感應(yīng)器 occupancy: 居住 占據(jù),2020/9/14,Good

40、good study,day day up!,22,17. Filter banks are ordinarily assembled vertically, and on large jobs the filters are usually of the cleanable type for use over and over again. 18. In systems requiring only one or two zones, where the air conditioning units can be located close to the cooling and heatin

41、g equipment, the usual practice is to use direct expansion (DX) refrigerant coil and hot-water coils.,direct expansion: 直接膨脹式,filter banks: 過濾器組 vertically: 垂直地,Topic Five: Text learning and keywords,2020/9/14,Good good study,day day up!,23,19. The entire housing for the centralstation air condition

42、ing unit is usually insulated over its outer-surface with at least 1-in-thick insulating board, all steam, hot-water, chilled-water, and suction refrigerant piping should be insulated to prevent heat losses and gains. 20. If air conditioning central systems are located on upper floors, it must be as

43、certained that the building stress design has taken these loads into account.,housing: 外殼 insulating board: 保溫板 suction: 吸入 condensate water 冷凝水,ascertain: 確保 building stress design: 建筑應(yīng)力設(shè)計,Topic Five: Text learning and keywords,2020/9/14,Good good study,day day up!,24,21. Quiet-operating fan motors

44、 should be specified, vibration dampers should be installed under all rotating equipment, and acoustic linings specified for mechanical rooms.,quiet-operating : 靜音型的 vibration damper: 減震器 acoustic linings: 隔音層,Topic Five: Text learning and keywords,22. Ducts and duct turns should be lined at critica

45、l places with acoustic board, and extreme care must be exercised in duct design so that high velocity whistle will not occur.,turns: 轉(zhuǎn)彎 acoustic board: 隔音板 line: 裝襯 填充 exercise: 行使 實施 whistle: 口哨聲,2020/9/14,Good good study,day day up!,25,23. Office buildings, hotels and motels, guest rooms, hospital

46、s, and apartment buildings are ordinarily air conditioned by the use of separate air conditioning units in each room. 24. Individual room-temperature control is a feature of such systems, and the design is such that drafts are minimized. The one disadvantage is the fact that the units themselves tak

47、e up floor space and interfere to some extent with room decor.,feature: 特點(diǎn) draft: 引申為氣溫波動 decor: 裝飾,office building: 辦公建筑 motels:汽車旅館 guest room: 客房 apartment building: 公寓建筑,2020/9/14,Good good study,day day up!,26,25. Summer humidity control is obtained by proper coil temperature and size, while some winter humidification is provided by the out