制冷原理双语版第九章
《制冷循环原理》课件
吸收式制冷循环
优点
对环境友好、能源消耗低、维护 方便。
缺点
效率较低、制冷量较小、调节困 难。
吸附式制冷循环
总结词
利用固体吸附剂吸附气体，产生低温，从而达到制冷效果。
详细描述
吸附式制冷循环是利用固体吸附剂吸附气体，产生低温，从而达到制冷效果的一种循环 方式。其原理是利用吸附剂在吸附过程中放出热量，然后通过冷凝器将热量传递给周围
实现制冷系统的快速响应和高效运行。
制冷技术在新能源领域的应用
新能源领域
随着新能源技术的不断发展，制冷技术在新能源领域 的应用也越来越广泛，如太阳能、风能等可再生能源 的利用，需要制冷技术作为支撑和保障。
技术融合
制冷技术与新能源技术的融合，可以实现能源的高效 利用和节能减排，推动能源结构的优化和可持续发展 。
掌握制冷循环原理是深入理解制冷技术、提高制冷设备性能和能效、解决实际 问题的关键。
01
制冷循环的基本原 理
制冷循环的组成
01
02
03
04
压缩机
用于压缩制冷剂，提高其压力 和温度。
冷凝器
用于将高温高压的制冷剂冷却 成液体。
膨胀阀
用于将高压液态制冷剂节流成 低温低压的湿蒸汽。
蒸发器
用于将低温低压的湿蒸汽吸热 ，使其蒸发成气体，从而降低
技术挑战
新型制冷技术的研发面临技术挑战，如材料 性能、系统稳定性、制造成本等问题，需要 科研人员不断探索和改进。
制冷技术的智能化与自动化
智能化
制冷技术的智能化是未来的发展趋势，通过 引入人工智能、物联网等技术，实现制冷系 统的自适应调节、远程监控和故障诊断等功 能，提高系统的稳定性和能效。
自动化
制冷原理课件
2.1.1 蒸气压缩式制冷循环
制 (一) 单级蒸气 冷 压缩式制冷循环 原
理
与
技 （二）多级蒸气 术 压缩式制冷循环
1．朗肯循环 2．劳伦茨循环 3．跨临界循环
双筒型煤油燃烧器 釜式燃烧器 蒸发燃烧器 燃油喷雾燃烧器
2.1.1 蒸气压缩式制冷循环
制
制冷循环就是通过一定的
冷 能量补偿，从低温热源吸热，
制
冷
原
理
与
技
术
图2-9 两级节流、具有中温蒸发器的中间完全冷却两级压缩制冷循环
( a ) 流程图
( b ) lgp-h图
制 冷 原 理 与 技 术
（四）复叠式蒸气压缩式制冷循环
制
定义
冷
由两个（或数个）不同制冷剂工作
原
的单级（也可以是多级）制冷系统组合
理
而成。
与
技
术
制 冷 原 理 与 技 术
最低蒸 发温度 -80℃
制 冷 原 理 与 技 术
制 冷 原 理 与 技 术
图2-7 两级节流、中间完全冷却的两级压缩制冷循环
( a ) 流程图
( b ) lgp-h图
制 冷 原 理 与 技 术
制
冷
原
理
与
技
术
图2-8 两级节流、中间不完全冷却的两级压缩制冷循环
( a ) 流程图
( b ) lgp-h图
制 冷 原 理 与 技 术
术 机 a2—高温部分低压级压缩机 a3—高温部分高压级压缩
机b—冷凝器 c1、c2、c3—节流阀 d—蒸发器 d12冷凝-
蒸发器e1—低温部分气-液热交换器 e2—高温部分气-液
热交换器 f—高温部分中间冷却器
图解制冷原理(内含动态原理图)
图解制冷原理（内含动态原理
图）
一、空调系统
首先是空调系统的使用。
我相信朋友们闭上眼睛也能说出原理。
二、冰箱系统
冰箱系统也是制冷系统最常见的应用。
我们来看看原理。
三、热泵系统
实际上，热泵系统是空调制冷系统的逆向应用方案。
之前用制冷制冷系统产生冷量，现在用四通换向阀产生热量。
我们来看一下原理图。
先来看看制冷模式：
再来看看热泵运行模式：
实际使用当中，最常见的还是风冷热泵机组了，看下面的原理图：
1.第一，制冷模式可以产生冷水。
如果连接空气末端设备，可以为房间提供冷能。
2、再来看看制热模式，早的很多年前，这个系统经过包装一下，摇身一变，变成一个非常时髦的概念叫空气源热泵系统，号称是第五代热水系统：
四、制冰机系统
制冰机也是制冷系统最常见的应用之一。
我们来看看制冰机的几种形式。
五、除湿机系统
当然，除湿机系统也是基于制冷系统的原理。
潮湿的空气被风扇吸入机器，并通过热交换器。
此时空气中的水蒸气凝结成水滴，而干燥的空气温度降低，排出机外。
六、汽车空调系统
汽车空调系统是制冷系统的经典用例，包括汽车空调系统、火车空调系统、公交车空调系统、冷藏车空调系统、冷藏集装箱等。
我们简单看一下:
七、冷藏展示柜
超市、餐厅的冰箱、展示柜也是利用制冷原理。
八、干冰机
干冰机也是利用制冷原理的哦。
制冷原理及装置
制冷原理及装置Refrigeration is a process of removing heat from a particular area or substance to lower its temperature. 制冷是一种从特定区域或物质中去除热量以降低温度的过程。
This principle is based on the fact that when a liquid evaporates, it absorbs heat from its surroundings, thus causing a drop in temperature. 这种原理是基于液体蒸发时会从周围吸收热量，从而导致温度下降。
The primary goal of refrigeration is to maintain a specific low temperature for various applications such as food preservation, air conditioning, and medical equipment. 制冷的主要目标是为了在食品保存、空调和医疗设备等各种应用中保持特定的低温。
This is achieved through the use of various techniques and devices designed to facilitate the transfer of heat. 这通过利用各种技术和设备来促进热量的传递来实现。
Refrigeration operates on the basic principle of thermodynamics, where heat is transferred from a lower temperature region to a higher temperature region. 制冷操作基于热力学的基本原理，在此热量从低温区域转移到高温区域。
制冷技术(英文版)Ch9-090604
Chapter 9. Psychrometry and Air Processes9-1) Composition and thermal properties of moist airordinary thermometer. The temperature of water vapor is the same as that of the dry air in moistair. Such a thermometer is called a dry-bulb thermometer in psychrometry, because its bulb is dry.b) Wet bulb temperature WB t : Wet bulb temperature is thermodynamic adiabatic temperatire in anadiabatic saturation process, and measured by a wet bulb thermometer. c) Dew point temperature DP t :When the unsaturated moist air is cooled at constant vapor pressure w p or at constant humidity ratio w , to a temperature, the moist air becomes saturated and the condensation of moisture starts, this temperature is called dew point temperature DP t of the moist air. The relation of dry-bulb, wet-bulb, and dew point temperatures:1. When the moist air is not saturated, the dewpoint temperature is lower than the dry-bulb temperature, and the wet-bulb temperature lies between them. That is DP WB t t t >>.2. As the moisture in the air increases, the differences between the temperatures become smaller.3. When the air is saturated, all three temperatures are the same. That is DP WB t t t ==.d) Relative humidity φ: Relative humidity is defined as the ratio of the mole fraction of the water vapor in a given moist air to the mole fraction of water vapor in a saturated moist air at the same temperature t and the same atmospheric pressure B . Relative humidity is usually expressed in percentage (%). From the ideal gas relations, relative humidity φ can be expressed assatw wsatw w P P x x ,,==φ (9-1) e) Degree of Saturation μ: Degree of saturation is defined as the ratio of the humidity ratio of moist air w to the humidity ratio of saturated moist air sat w at the same temperature and atmosheric pressure.wsat w sat P B P B w w--⨯==,φμ (9-2)The difference between relative humidity φ and degree of saturation μ is usually less than 2%.f) Humidity ratio (Moisture Content)w : The humidity ratio is the mass kg of water vaporinterspersed in each kg of dry air. It should be noted that the mass of water refers only to the moisture in actual vapor state, and not to any moisture in the liquid state, such as dew, frost, fog or rain. The humididy ratio, like other several properties to be studied- enthalpy and specific volume-is based on 1kg of dry air.)()(a i rd r y of kg m vapor water of kg m w a w ⋅⋅⋅⋅⋅⋅=(9-3)湿空气的热物理性质是按照理想气体计算的In most applications of air conditioning and food refrigeration, both dry air and water vapor in moist air may be assumed as perfect gases.Dry air is assumed to be a perfect gas because its temperature is quite high relative to its saturation temperature, and water vapor is assumed to be a perfect gas because its pressur is quite low relative to its saturation pressure .[1] 湿空气的热物理性质是按照理想气体计算的T R m V P w w w = and T R m V P a a a = (9-4)wwa w w w a a w w a a w w a w P B P R P B R P R P R P T R V P T R V P m m w -=-====622.0/)(///)/()/( (9-5) g) Specific Volume/Moist Volume v : Specific volume of moist air v , dry kg m /3 is defined asthe total volume of the moist air (dry air and water vapor mixture) per kg of dry air.))(())(273()/(7.286Pa P B K t K kg J P T R v w air dry a -+⨯⋅==⋅, air dry kg m ⋅/3 (9-8) h) Specific Enthalpy : Specific enthalpy of moist air h (dry kg kJ /) is defined as the total enthalpy of the dry air and water vapor mixture per kg of dry air. Enthalpy values are always based on some datum plane. Usually the zero value of the dry air is chosen as air at 0C 0, and the zero value of the water vapor is the saturated liquid water at 0C 0.The thermal properties of saturated water are shown in Tab.9-2; and the thermal properties of saturated moist air at atmosphere of 101kPa are shown in Tab.9-3.Note: The data of saturation pressure, specific volume and latent heat of evaporation are from experiments. The data of enthaly are from calculation, and the zero value of the enthalpy is set for the saturated liquid water at 0C0.Note: The data of saturation pressure are from experiments. The data of humidity ratio, specific volum are from calculation. The data of enthaly are calculated based on the properties experiment of air and water vapor. And the zerovalue of the dry air is chosen as air at 0C0, the zero value of the water vapor is the saturated liquid water at 0C0.(1) Adiabatic saturation processwet-bulb temperature)Fig.9-1, An adiabatic saturation processAn unsturated air, which has dry bulb temperature 1t , humidity ratio 1w and enthalpy 1h , flows through a spray of water, as shown in Fig.9-1. The spray can provide enough surface area so that the air leaves the spray chamber in equilibrium with the water, with respect to both the temperature and the vapor pressue.In order to perpetuate the process, it is necessary to provide makeup water )(12w w - to compensate for the amount of water evaporated into the air. The temperature of the makeup water is the same as that in the sump.If the device is adiabatic, then the process is called adiabatic saturation process.In an adiabatic saturation process, the temperature of the water in the sump is called thethermodynamic wet bulb temperature WB t of the air , or simply the wet bulb temperature of the air. An adiabatic saturation process is a constant wet bulb temperature process, the wet bulb temperatures of air at the inlet and the outlet are same, and they are equal to WB t . That is 21⋅⋅=WB WB t tA simple wet bulb thermometer used to measure the wet bulb temperature is based on the principle of the adiabatic saturation process. It is an ordinary thermometer being wrapt with a cloth sleeve of wool or flannel, around its bulb. The cloth sleeve should be clean and free of oil andthoroughly wet with clean fresh water. The water in the cloth sleeve evaporates as the air flows at a high velocity (sec /5.2m ≥). The evaporation, which takes the heat from the thermometer bulb, lowers the temperature of the bulb. The thermometer indicates approximately the wet bulb temperature WB t . The difference between the dry-bulb and wet-bulb temperatures is called the wet-bulbdepression. If the air is saturated, evaporation cannot take place, and the wet-bulb temperature is the same as the dry-bulb temperature; and the wet-bulb depression equals zero.If two independent parameters which indicate the state of moist air are known, the thermal properties can be calculated by approximate methods. For example, if the temperature t and relative humidity φof a moist air are known at 27C 0 and 50%, respectively, the other properties can be calculated as follows.(1) Partial pressure of vapor in moist air w pFrom Tab.9-2 or Tab.9-3, it can be found that the saturation pressure sat w p ,of water for 27C 0is3.5649kPa .Alternatively, the saturation pressure over the range between 0ºC to +45ºC can also be estimated fromthe following formula:35242,1013.61040.51096.4610.0t t t P sat w ⨯⨯+⨯⨯+⨯⨯+=--- (9-10)where t is temperature in °C ; sat w p , in kPa .For t =27C 0, the saturation pressure sat w p ,=3.55 kPa calculated from Eq.(9-10). And from Eq. (9-1), sat w w p p ,⨯=φ = 3.565⨯50%=1.78 kPa .(2) Humidity ratio w : From Eq.(9-5),air dry w w w kg kg P B P w ⋅⋅=-=-=/0111.078.13.10178.1622.0622.0 (3) Dew point temperature DP t :The dew point temperature is the temperature at which the moist air becomes saturated and starts to condense at constant vapor pressure w p or constant humidity ratio w . Therefore, when the vapor pressure w p or constant humidity ratio w is known, the dew point temperature can be found from Tab.9-3 in the corresponding saturation temperature column. For w p =1.78 or w =0.0111, the dew point temperature DP t is, therefore, DP t =15.7C 0(4) Specific Volume v : From Eq.(9-8)864.0)78.133.101()271.273(7.286))(())(273()/(7.286=-+⨯=-+⨯⋅==⋅Pa P B K t K kg J P T R v w air dry a air dry kg m ⋅/3 (5) Specific enthalpy h : As the enthalpy of moist air h is the total enthalpy of the dry air and watervapor mixture per kg of dry air, and the enthalpy of dry air at 0C 0is chosen as zero, the enthalpy of saturated liquid water at 0C 0 is chosen as zero, therefore the specific enthalpy of moist air can be calculated from the following equation,vapor h w t Cp h ⨯+⨯= (9-11)where Cp is the specific heat of dry air , it is 1.003 )/(K kg kJ ⋅ for the temperatures from 0C 0 to50C 0as shown in Tab.9-1; w is the humidity ratio.In the case of air-conditioning, the following approximation is valid)()(.t h t h v a p o rs a t v a p o r ≈ (9-12) Where vap h is the enthalpy of superheated vapor; and sat vap h , is the enthalpy of saturated water vapor at the same temperature. That is, the enthalpy of superheated vapor is nearly the same as the saturatedvapor at same temperature.The enthalpy of saturated water vapor can also be approximately calculated from the following formulat t h vapor sat ⨯+=82.14.2501)(. (9-13)By using equation (9-13), the enthalpy of moist air can be found from the formula below)82.14.2501(003.1t w t h ⨯+⨯+⨯= (9-14)For the moist air at t = 27C 0and φ=50%, its enthalpy h is found from Eq.(9-14) :6.55)2782.14.2501(0111.027003.1=⨯+⨯+⨯≈h a i rd r y kg kJ ⋅/ (6) Wet bulb temperature : Since a constant wet bulb temperature process is nearly a constantenthaly process, the wet bulb temperature WB t can be found from the enthapy of 55.6 from Tab.9-3.This gives the wet bulb temperature WB t = 19.43 C 0.A psychrometric chart graphically represents the thermodynamic properties of moist air, as shown in Fig.9-2. It is very useful in presenting the air conditioning processes.The psychrometric chart is bounded by two perpendicular axes and a curved line: 1. The horizontal ordinate axis represents the dry bulb temperature line t , in C 0; 2. The vertical ordinate axis represents the humidity ratio line w , in air dry w kg kg ⋅/ ; 3. The curved line shows the saturated air, it is corresponding to the relative humidity%100=φThe psychrometric chart incorporates seven parameters and properties. They are dry bulb temperature t , relative humidity φ, wet bulb temperature WB t , dew point temperature DP t , specific volume v , humidity ratio w and enthalpy h .1, Dry-bulb temperature t is shown along the bottom axis of the psychrometric chart. The vertical lines extending upward from this axis are constant-temperature lines. 2, Relative humidity lines φ are shown on the chart as curved lines that move upward to the left in 10% increments. The line representing saturated air (φ = 100%) is the uppermost curved line on the chart. And the line of φ = 0% is a horizontal ordinate axis itself.3, Wet-bulb temperaturet: On the chart, the constant wet-bulb lines slope a little upward to the left,WBand the wet bulb temperature is read following a constant wet-bulb line from the state-point to the saturation line.4, Dew point temperaturet: This temperature is read by following a horizontal line from theDPstate-point to the saturation line.5，Specific volume v: It is shown from the constant-volume lines slanting upward to the left.6, Humidity ratio w: it is indicated along the right-hand axis of the chart.7, Enthalpy h: It is read from where the constant enthalpy line crosses the diagonal scale above the saturation curve. The constant enthalpy lines, being slanted lines, are almost coincidental as the constant wet-bulb temperature lines.Fig.9-2, Psychrometric Chart (B=101.3 kPa)Only two properties are needed to characterize the moist air because the point of intersection of any two properties lines defines the state-point of air on a psychrometric chart. Once this point is located on the chart, the other air properties can be read directly.Exampleas shown in Fig.9-3: For a moist air with dry-bulb temperature C t 027= and relative humidity %50=φ, other parameters and properties found from the psychrometric chart are:Wet-bulb temperature : WB t = 19.6 C 0; dew-point temperature: DP t = 15.8 C 0; specific volume: air dry kg m v ⋅=/865.03;khumidity ratio: air dry w kg kg w ⋅=/0113.0;（图上的数字也要改成0.0113）specific enthalpy: air dry kg kJ h ⋅=/5.55(s at ur at io nt e mp ,℃)l i ne h um id i t yr e la t iv es a tu ra t i o n φ=50%φ=100%E nt ha lp yhhs p e c i f i c v o l u m eh=55.65v =0.88v =0.86v =0.865w e t-b ul b te mph u m i d i t y r a t i o ww=0.113dry-bulbtemp27℃wet-bulb temp 19.6℃ dew point temp 15.8℃Fig.9-3, Determination of the properties from psychrometric chart.C t C 002722≤≤;relative humidity: %60%40≤≤φ; air flow rate:sec /25.0m ≈.a) Sensible cooling along a cooling coil, or sensible heating along a heating coilThe sensible cooling happens when the air is cooled without altering the specific humidity. The process is shown on the psychrometic chart by line 1a in Fig.9-4. During this process, the relative humidity of the air will increase. The sensible cooling can only take place under the condition when the temperature of the cooling coil is not below the dew point temperature of the air being processed.W BDphu mi di tyφre la ti v eφ=100%32b2a1b 1aw h u m i d i t y r a t i otw et -b ul b te mpt dry-bulb tempdew-point tempFig.9-4, Main air handing processes and their variations in propertiesThe sensible heating is similar to sensible cooling, but with the dry bulb temperature increasing (line 1b in Fig.9-4). It should be noted that there should be no water within the heating system because the evaporation of the water will increase the specific humidity of the air.b) Adiabatic humidification and dehumidification using a humidifier or chemical dehumidifierThe adiabatic humidification occurs when water vapor, of which temperature is near the wet bulb temperature of the moist air, is added to the air (line 2a in Fig.9-4). A humidifier performs this function by supplying the water vapor. During the adiabatic humidification process along the constant wet bulb temperature line, the specific humidity of air will increase. Reduction in dry bulbtemperature will happen as the evaporated water will absorb heat.The adiabatic dehumidification is a reverse process of the humidification, as shown by line 2b in Fig.9-4. This dehumidification is usually achieved by use of chemical agents, like absorbents or adsorbents. In this process, the specific humidity decreases along the constant wet bulb temperature line, whilst the dry bulb temperature will increase, as a result of chemical reaction c) Cooling with change in specific humidity using conventional air conditionersWhen the temperature of evaporator is lower than the dew point temperature of the entering air, some water vapor in the air will condense and drain off. The dry bulb temperature and the specific humidity of the air will reduce. This process can be shown by line 3 on the psychrometric chart in Fig.9-4.When the temperature of evaporator is lower than the dew point temperature of the entering air, some water vapor in the air will condense and drain off. The dry bulb temperature and the specific humidity of the air will reduce, this process can be shown by line 3 on the psychrometric chart in Fig.9-4.There are a lot of heat exchangers in refrigeration and air conditioning systems. Moist air makes heat transfer and/or mass transfer with the solid surface of the heat exchangers. If the solid surface is dry during the process, there is heat transfer only. However, if the solid surface is wetted, there are both heat transfer and mass transfer.In the following discussions, we assume that the moist air has properties: dry bulb temperature a t , humidity ratio a w , and enthalpy a h ; and the water layer on a wetted surface of a solid heat exchanger has properties: temperature s t , humidity ratio s w and enthalpy s h .The sensible heat transfer rate sensible dq , kW , from the wetted surface to the moist air is)(a s sensible t t dA dq -⋅⋅=α (9-17)where αis convection heat transfer coefficient, )/(2K m kW ⋅; A is the heat transfer area, 2m .The mass transfer rate of water vapor dm , s kg w /, from the wetted surface to the moist air is)(a s w w dA D dm -⋅⋅= (9-18)where D is water vapor diffusion coefficient, )/(2s m kg ⋅;The latent heat transfer rate latent dq , kW ,from the wetted surface to the moist air isfg a s latent h w w dA D dq )(-⋅⋅= (9-19)where fg h is latent heat of water evaporation, w kg kJ /If the heat transfer of a flow over a surface of heat exchanger can be described as the following non- dimensional formula11(Pr)(Re)/1m n C k x Nu =⋅=α (9-20)And the mass transfer of a flow over a surface of heat exchanger can be described as the following non- dimensional formula22)((Re)/2m n D Sc C k x D Sh =⋅= (9-21)where Nu is Nusselt number; Sh is Sherwood number; Re is Reynolds number, kCp⋅=μPr is Prandtl number; Dk Sc ⋅=ρμis Schmidt number, μis dynamic viscosity,k is thermal conductivity, D k is mass transfer diffusion coefficient.刘易斯数是湿空气的物性 The Lewis number N Le is a property of a mixture. For moist air, Lewis number N Le has values not far from 1. [3]In order to relate the heat transfer process, Eq.(9-20), with the mass transfer process, Eq.(9-21), a new nondimensional,刘易斯数是关联传热和传质2个过程(9-23)where air moist Cp ⋅is the specific heat of moist air; αis heat transfer coefficient; D is mass transfer coefficient.. Lewis factor f Le is not a property of moist air, it is variable with the conditions of heat andmass transfer. The value of Lewis factor f Le is considered in the region of 0.5-1.3. [4]In many air conditioning cases, the Eq.(9-18) and Eq.(9-19) have completely similar form, that is212121;;m m n n C C ===,. Therefore we can assume Lewis factor f Le =1.0, thenair moist Cp D ⋅=/α (9-24)where air moist Cp ⋅is the specific heat of moist air,)/(K kg kJ ⋅The total heat transfer rate, sensible and latent heat transfer, from the wetted surface to the moist air is available from a combination of Eqs.(9-17) and (9-19)fg a s a s latent sensible total h w w dA D t t dA dq dq dq ⋅-⋅⋅+-⋅⋅=+=)()(α (9-25)Applying the Lewis factor f Le =1.0 and the Eq. (9-25) can be written asfg a s airmoist a s total h w w dA Cp t t dA dq ⋅-⋅⋅+-⋅⋅=⋅)()(αα=)]()[(fg a a air moist fg s s air moist airmoist h w t Cp h w t Cp Cp dA+⋅-+⋅⋅⋅⋅⋅α (9-26)For dry air, specific heat )/(003.1K kg kJ Cp air dry ⋅=⋅;For moist air, specific heat vapor erheated air dry air moist Cp w Cp Cp ⋅⋅⋅⨯+=sup . For the most cases of airconditioning )/(0.2sup K kg kJ Cp vapor erheated ⋅=⋅; air dry kg kg w ⋅⋅-=/)014.0007.0(.)/(02.1K kg kJ Cp air moist ⋅≈⋅ and )(t h wh t Cp fg air moist ≈+⋅⋅. Therefore(9-27)Therefore the concept of enthalpy potential is a very useful one in quantifying the total heattransfer in those processes where there is direct contact between air and water.If a t >s t , the sensible heat s dq is from the moist air to the solid surface; If a w >s w , the mass and latent heat is from the moist air to the solid surface;If a h >s h or WB a t ,>WB s t ,, the total heat total dq is from the moist air to the solid surface.References1, Stoecker W.F., Jones J.W., Refrigeration and air conditioning, 2nd Edition, McGraw-Hill Book Company, New York, USA, 19822, ASHRAE, ASHRAE Handbook-Fundamental, New York, USA, 20053, Eckert E.R.G., Drake R.M., Analysis of heat and mass transfer, McGraw-Hill Ltd, New York, USA, 19724. Kloppers J.C., Kroger D.G., The Lewis factor and its influence on the performance prediction ofwet-cooling towers, International Journal of Thermal Science, (44),879-884, 2005。
制冷原理(中英文对照)
制冷原理培训教材Refrigeration principletraining material一：制冷原理简介Refrigeration principle本系统属于蒸汽压缩式制冷循环，主要包括压缩机、冷凝器、毛细管、干燥过滤器、蒸发器5个部件，经过压缩、冷凝、节流、蒸发四个过程不断循环，制冷剂周期性的发生从蒸汽变为液体，从液体变为蒸汽的状态变化，不端的把冰箱内的热量转移到冰箱外部，从而达到制冷目的。
The appliance incorporates a vapor compressor refrigeration system that consists of compressor, condenser, capillary, filter drier and evaporator and accomplishes the refrigeration through the cycle of compression, condensation, throttling, and evaporation. The process repeats and extracts the heat from the fridge compartment by having the refrigerant evaporated in the evaporator and liquefied in the condenser.二：主关件简介：Main components(一)：压缩机Compressor制冷系统的“心脏”，起压缩和输送制冷剂的作用，目前所用为往复活塞式压缩机。
Serving as the heart of the refrigeration system, the compressor functions through compressing and passing the refrigerant. A reciprocal compressor is adopted in the system.主要性能指标Performance1:制冷量:压缩机工作时,每小时从被冷却物体带走的热量以(千焦/小时)活或瓦表示.制冷量大小随工况条件变化,工况条件不同制冷量大小不同.1. Cooling capacity: refer to the heat in kilojoule/hour extracted from the articles to be cooled down in an hour. The cooling capacity changes along with the operating conditions.2.功率.是指压缩机每小时耗功的大小.Power: refer to hourly power consumption of the compressor.3.性能系数COP:性能系数就是制冷量与:压机输出功率大小之比,COP越大说明耗电量越小,冰箱越节能.COP: refer to the cooling capacity – output power ratio. The higher the COP value, the lower the energy consumption.压缩机三个重要附件:Three essential accessories:1.启动控制器Start control电冰箱刚开始启动时,PTC元件温度较低,电阻小,启动绕组接通,由于启动电流大,PTC温度随之升高,当达到临界温度电阻猛增到数万欧姆,可视为断路.于是与之串联的起动绕组断电,运转绕组正常工作.PTC是一种无触电开关,但停机后由于PTC温度仍很高,所以无法马上启动.The PTC element has a low temperature and small resistance when the appliance starts. The starting winding is energized. The PTC temperature rises along with the increase of the starting current and reaches the threshold temperature when the resistance comes up to thousands of ohms, which is deemed as an open circuit. Then the starting winding in series with the PTC opens and the running winding works normally. PTC is a no-touch switch. When the appliance is turned off, it cannot start immediately because the PTC temperature is still very high.2.过载保护器Overload protector过载保护器是用来防止压缩机过载和过热而烧毁电动机而设置的,海尔压机一般采用碟形保护器.The overload protector is used to prevent overheating of the compressor that may cause burning-out of the motor. Haier compressor generally usebutterfly protector.3.启动电容器Starting capacitor(二). 冷凝器Condenser冷凝器将从蒸发器中吸收的热量连同压机耗工所转化的热量在冷凝器中释放到空气中,使压缩机排出的过热蒸汽冷却为过冷液体.The refrigerant parts with its heat absorbed from the evaporator and the waste heat produced during the operation of the compressor. The heat is released into the open air and the overheat vapor from the compressor is condensed into overcool liquid.1.内藏式冷凝器是由铜管制成的盘管贴附在U壳内侧而成.The condenser consists of coils made of copper pipe affixed to the U-shaped shell .(三).干燥过滤器Filter drier干燥过滤器是利用“分子筛”的吸附作用来去除制冷系统中的水分,酸质机杂质,以防止制冷系统冰堵或脏堵,一般采用钎焊焊接在冷凝器出口和毛细管之间.The working principle of filter drier is to make use of the absorption action of molecular sieve to remove the moisture and impurities fromthe refrigeration system against blockage due to ice or impurities. The filter drier is usually soldered between the condenser outlet and the capillary tube.(四).毛细管Capillary tube毛细管是制冷系统的节流装置,一般内径0.6-2.0MM,长度1.5-4.0M.毛细管因为细而长,所以对制冷剂有一定阻力，一方面可使制冷剂降压，一方面又可在一定范围内限制流量，有一定的自补偿能力，在冰箱停止运转后，可起均压作用，使高低压压力趋向平衡，便于下次启动。
制冷原理与设备9-2
9.2热力膨胀阀
9.2热力膨胀阀
9.2.1 内平衡式热力膨胀阀
内平衡式热力膨胀阀由阀体、推杆、阀座、 阀针、弹簧、调节杆、感温包、联接管、感 应膜片等部件组成。
9.2热力膨胀阀
ห้องสมุดไป่ตู้
9.2热力膨胀阀
9.2热力膨胀阀
9.2热力膨胀阀
9.2热力膨胀阀
9.2热力膨胀阀
9.2热力膨胀阀
9.2热力膨胀阀
内平衡式热力膨胀阀
9.2热力膨胀阀
9.2热力膨胀阀
9.2 热力膨胀阀
热力膨胀阀普遍用于氟利昂制冷系统中，通过感 温机构的作用，随蒸发器出口处制冷剂的温度变 化而自动变化，达到调节制冷剂供液量的目的。
热力式膨胀阀主要由阀体、感温包和毛细管组成。 热力式膨胀阀按膜片平衡方式不同有内平衡式和 外平衡式两种类型。
9.2热力膨胀阀
制冷原理PPT课件
水在系统中的危害
在低温系统中产生 冰堵，影响系统正常 运行。 降低电动机绝缘电阻，危及系统安全。 对金属的腐蚀加剧，使机器设备的寿命 缩短。 冷量减少，功耗增加。
水在系统中的危害
： 会产生如下化学反应
CCL２F２＋H２O→2HCL+2HF+CO２-----------------------------------1 FE＋2HCL→FECL２＋H２↑----------------------------------------------- 2 ECL２＋2HCL→ FE（OH２）＋2HCL ---------------------------------- 3 2FE(OH)２＋ H２O+O →2FE(OH)２ ---------------------------------------4 当有铜材存在时 〖O〗+2HCL+2CL→2CUL＋H２O FE＋2CUCL→FECL２＋2CU（产生游离态的铜分子，在钢铁材料表 面产生镀铜现象）。
错误的温包安装方式１
感温包应绑在回热交换器之前
错误的温包安装方式２
感温包应该绑扎在蒸发器出口处的水平 管段，不能在竖直管段。
错误的温包安装方式３
感温包应绑在回油弯之前。
蒸发的概念
升华 凝固 蒸发 沸腾 冷凝
固态－气态 液态－固态 液态－气态 液态－气态 气态－液态
蒸发器的作用
液态制冷剂经节流后在蒸发器中气化吸 热，使被冷却介质的温度降低，达到制 冷的目的。
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制冷原理(中英文对照)
制冷原理培训教材Refrigeration principle training material一：制冷原理简介Refrigeration principle本系统属于蒸汽压缩式制冷循环，主要包括压缩机、冷凝器、毛细管、干燥过滤器、蒸发器5个部件，经过压缩、冷凝、节流、蒸发四个过程不断循环，制冷剂周期性的发生从蒸汽变为液体，从液体变为蒸汽的状态变化，不端的把冰箱内的热量转移到冰箱外部，从而达到制冷目的。
The appliance incorporates a vapor compressor refrigeration system that consists of compressor, condenser, capillary, filter drier and evaporator and accomplishes the refrigeration through the cycle of compression, condensation, throttling, and evaporation. The process repeats and extracts the heat from the fridge compartment by having the refrigerant evaporated in the evaporator and liquefied in the condenser.二：主关件简介：Main components(一)：压缩机Compressor制冷系统的“心脏”，起压缩和输送制冷剂的作用，目前所用为往复活塞式压缩机。
Serving as the heart of the refrigeration system, the compressor functions through compressing and passing the refrigerant. A reciprocal compressor is adopted in the system.主要性能指标Performance1:制冷量:压缩机工作时,每小时从被冷却物体带走的热量以(千焦/小时)活或瓦表示.制冷量大小随工况条件变化,工况条件不同制冷量大小不同.1. Cooling capacity: refer to the heat in kilojoule/hour extracted from the articles to be cooled down in an hour. The cooling capacity changes along with the operating conditions.2.功率.是指压缩机每小时耗功的大小.Power: refer to hourly power consumption of the compressor.3.性能系数COP:性能系数就是制冷量与:压机输出功率大小之比,COP越大说明耗电量越小,冰箱越节能.COP: refer to the cooling capacity –output power ratio. The higher the COP value, the lower the energy consumption.压缩机三个重要附件: Three essential accessories:1.启动控制器Start control 电冰箱刚开始启动时,PTC元件温度较低,电阻小,启动绕组接通,由于启动电流大,PTC温度随之升高,当达到临界温度电阻猛增到数万欧姆,可视为断路.于是与之串联的起动绕组断电,运转绕组正常工作.PTC是一种无触电开关,但停机后由于PTC温度仍很高,所以无法马上启动.The PTC element has a low temperature and small resistance when the appliance starts. The starting winding is energized. The PTC temperature rises along with the increase of the startingcurrent and reaches the threshold temperature when the resistance comes up to thousands of ohms, which is deemed as an open circuit. Then the starting winding in series with the PTC opens and the running winding works normally. PTC is a no-touch switch. When the appliance is turned off, it cannot start immediately because the PTC temperature is still very high.2. 过载保护器Overload protector 过载保护器是用来防止压缩机过载和过热而烧毁电动机而设置的,海尔压机一般采用碟形保护器.The overload protector is used to prevent overheating of the compressor thatmay cause burning-out of the motor. Haier compressor generally use butterfly protector.3.启动电容器Starting capacitor(二). 冷凝器Condenser 冷凝器将从蒸发器中吸收的热量连同压机耗工所转化的热量在冷凝器中释放到空气中,使压缩机排出的过热蒸汽冷却为过冷液体.The refrigerant parts with its heat absorbed from the evaporator and the waste heat produced during the operation of the compressor. The heat is released into the open air and the overheat vapor from the compressor is condensed into overcool liquid.1.内藏式冷凝器是由铜管制成的盘管贴附在U壳内侧而成.The condenser consists of coils made of copper pipe affixed to the U-shaped shell .(三).干燥过滤器Filter drier 干燥过滤器是利用“分子筛”的吸附作用来去除制冷系统中的水分,酸质机杂质,以防止制冷系统冰堵或脏堵,一般采用钎焊焊接在冷凝器出口和毛细管之间.The working principle of filter drier is to make use of the absorption action of molecular sieve to remove the moisture and impurities from the refrigeration system against blockage due to ice or impurities. The filter drier is usually soldered between the condenser outlet and the capillary tube.(四).毛细管Capillary tube 毛细管是制冷系统的节流装置,一般内径0.6-2.0MM,长度1.5-4.0M. 毛细管因为细而长,所以对制冷剂有一定阻力，一方面可使制冷剂降压，一方面又可在一定范围内限制流量，有一定的自补偿能力，在冰箱停止运转后，可起均压作用，使高低压压力趋向平衡，便于下次启动。
###Refrigeration cycle 制冷原理(英文)
2PRD-002A
Refrigeration is the process of removing heat from one substance and transferring it to another substance.
The term refrigeration is commonly associated with something cold. A household refrigerator, for example, keeps food cold. It accomplishes this task by removing heat from the food. Therefore, refrigeration involves the removal of heat. The word cold describes a state of low heat content. To understand how refrigeration works, we first need to understand what heat is and how it is removed from a substance.
1/52 Copyright ⓒ 2006 All rights reserved LG Electronics Inc.
What is Heat?
2PRD-002A
Heat is a form of energy
What is Heat?
Heat is a form of energy. Every object on earth contains heat energy in both quantity and intensity.
8/52 Copyright ⓒ 2006 All rights reserved LG Electronics Inc.
制冷系统的组成和工作原理
制冷系统的组成和工作原理Refrigeration systems are an essential part of everyday life, providing us with comfort and convenience in our homes and workplaces. 制冷系统是日常生活中不可或缺的一部分，为我们的家庭和工作场所提供了舒适和便利。
The basic components of a typical refrigeration system include a compressor, condenser, expansion valve, and evaporator. 典型制冷系统的基本组件包括压缩机、冷凝器、膨胀阀和蒸发器。
The compressor is responsible for pressurizing and circulating the refrigerant, which is the substance that absorbs and releases heat to provide cooling. 压缩机负责增压和循环制冷剂，制冷剂是一种吸收和释放热量以提供冷却的物质。
Once the refrigerant is pressurized, it moves to the condenser, where it is cooled and condensed from a gaseous to a liquid state.一旦制冷剂被增压，它就会流向冷凝器，在那里它被冷却并从气态凝结为液态。
From the condenser, the refrigerant then moves through the expansion valve, where its pressure is reduced, allowing it to evaporate and absorb heat from the surrounding environment. 从冷凝器出来后，制冷剂通过膨胀阀，减少压力，使其蒸发并吸收周围环境的热量。
混合工质制冷原理
混合工质制冷原理The principle of mixed refrigerant is a fascinating concept that combines multiple refrigerants to enhance the overall efficiency of the cooling process. 混合工质制冷原理是一个引人入胜的概念，它将多种制冷剂组合在一起，以提高整个冷却过程的效率。
By blending different refrigerants with complementary characteristics, the mixed refrigerant system can achieve a wider range of operating temperatures and pressures. 通过混合具有互补特性的不同制冷剂，混合制冷系统可以实现更广泛的操作温度和压力范围。
One of the main advantages of using mixed refrigerants is the ability to tailor the system to specific cooling requirements, allowing for better performance and energy efficiency. 使用混合制冷剂的主要优势之一是能够根据具体的冷却需求来量身定制系统，从而实现更好的性能和能效。
Furthermore, mixing refrigerants can help to mitigate issues such as refrigerant compatibility, lubricant selection, and system design, leading to a more robust and reliable cooling solution. 此外，混合制冷剂可以帮助解决制冷剂兼容性、润滑剂选择和系统设计等问题，从而实现更稳健可靠的冷却解决方案。
制冷工系统作原理
制冷工系统作原理Refrigeration is a process that removes heat from a space or substance to lower its temperature. 制冷是一种过程，它从空间或物质中移除热量以降低其温度。
It is an essential system in various industries, including food storage, chemical processing, and HVAC (Heating, Ventilation, and Air Conditioning). 在食品储存、化工加工和暖通空调等各个行业中，制冷系统都是必不可少的。
The primary function of a refrigeration system is to maintain a specific temperature within a controlled environment. 制冷系统的主要功能是在受控环境中保持特定的温度。
This is achieved through a combination of mechanical, thermal, and chemical processes. 这通过机械、热力和化学过程的结合来实现。
Understanding the principles behind refrigeration systems can provide valuable insights into how they work. 了解制冷系统背后的原理可以提供宝贵的见解，深入了解它们的工作原理。
At the core of a refrigeration system is the refrigerant, a substance with a low boiling point that can easily absorb and release heat. 制冷系统的核心是制冷剂，这是一种具有低沸点的物质，可以轻易吸收和释放热量。
制冷专业英语课件.ppt
蒸汽轮机
Exercise(1)
Answer the following questions according to the text.
(1) How do we usually do when studying a thermal engineering?
(2) How can be the boundary of a system? (3) What is the solution of a system dependent on? (4) Based on the difference of the characteristic of
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Text 1 Thermodynamic System
New words
In the thermal engineering, the studied objects normally are isolated from oneБайду номын сангаасanother and then we try to analysis the change and interaction, the studied objects isolated is named thermodynamic system.1
(2) The boundary of a system can be either real or imaginary, but it can not be either fixed or movable.
制冷原理一
40 1533.50 0.00088392 0.0151351 249.69 416.56 1.1666 1.6995
50 1942.30 0.00092193 0.0116693 263.26 417.84 1.2081 1.6864
60 2426.60 0.00096878 0.0090006 277.59 418.09 1.2504 1.6721
热量传递的三种基本形式： 导热：同一(tóngyī)物体的不同部分之间和相互接触的不同 物体之间。 对流：流体与固体表面之间或流体内部，流体运动。 辐射：热辐射，电磁波。
传热：一种(yī zhǒnɡ)流体通过一定厚度的固体将 热量传给另 一种(yī zhǒnɡ)流体。
12
第十二页，共45页。
热工基础知识 - 导热(dǎorè)材料和 隔热材料
R22饱和液体及蒸汽热力性质简表
toC pa kPa υ' m3/kg υ" m3/kg h' kJ/kg h" kJ/kg s' kJ/(kg.K) s" kJ/(kg.K)
-5 421.35 0.00076831 0.0553394 194.18 403.50 0.9787
1.7593
0 497.59 0.00077834 0.0471354 200.00 405.36 1.0000 1.7528
18
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热工基础知识 - 升高(shēnɡ ɡāo)饱和点
压力(yālì)锅防止蒸汽 逃逸。 液体表面压力(yālì)升 高使液体的沸点升高
水沸腾(fèiténg)
1.208bar 105°C
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热工基础知识 - 降低(jiàngdī)饱和点
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Part 3. The Working Substances for RefrigerationChapter 9. Psychrometry and Air Processes第九章. 湿度测定和空气过程9-1 Composition and thermal properties of moist air 李增扬independent parameter to indicate the water content in the mixture. It may be one of the following parameters: the humidity ratio, the relative humidity, the wet bulb temperature, or the dew point temperature and others.在一定压力下的湿空气需要两个相互独立的参数来表示它的状态。
除了空气的温度(通常叫作干球温度)，通常还有一个独立的表示混合物中水蒸气含量的参数。
它可以是下面参数中的一个：含湿量，相对湿度，湿球温度或者露点温度或其他参数。
(1) Dry bulb temperature t :Dry bulb temperature is the temperature of the air, as measured by an ordinary thermometer. The temperature of water vapor is the same as that of the dry air in moist air. Such a thermometer is called a dry-bulb thermometer in psychrometry, because its bulb is dry.(1) 干球温度t ：干球温度用普通温度计测量的空气温度。
在湿空气中水蒸气的温度和干空气的温度相等。
这样的温度计在温度测量中叫作干球温度计，因为它的小球是干的。
(2) W et bulb temperature WB t :Wet bulb temperature is thermodynamic adiabatic temperature in an adiabatic saturation process, and measured by a wet bulb thermometer. The wet bulb temperature will be discussed in the next paragraph.(2) 湿球温度WB t ：湿球温度是由湿球温度记测量的在绝热饱和过程下的热力绝热温度。
湿球温度将在下一章讨论。
(3) Dew point temperature DP t :When the unsaturated moist air is cooled at constant vapor pressure w p or at constant humidity ratio w , to a temperature, the moist air becomes saturated and the condensation of moisture starts, this temperature is called dew point temperature DP t of the moist air.(3) 露点温度DP t ：当不饱和湿空气在恒定蒸气压力w p 或恒定含湿量w 下冷却到一定温度，使得湿空气变为饱和状态并开始结露，那么这个温度就叫湿空气的露点温度DP t 。
The relation of dry-bulb, wet-bulb, and dew point temperatures: 干球温度，湿球温度和露点温度的关系为：1) When the moist air is not saturated, the dew point temperature is lower than the dry-bulb temperature, and the wet-bulb temperature lies between them. That is DP WB t t t >>.1) 当湿空气不饱和时，露点温度小于干球温度，而湿球温度在两者之间。
即DP WB t t t >>。
2) As the moisture in the air increases, the differences between the temperatures become smaller. 2) 随着空气中湿气的增加，各个温度间的差距变小。
3) When the air is saturated, all three temperatures are the same. That is DP WB t t t ==. 3) 当空气饱和时，三个温度相等。
即DP WB t t t ==。
(4) Relative humidity φ:Relative humidity is defined as the ratio of the mole fraction of the water vapor in a given moist air to the mole fraction of water vapor in a saturated moist air at the same temperature t and the sameatmospheric pressure B . Relative humidity is usually expressed in percentage (%). From the ideal gas relations, relative humidity φ can be expressed as(4) 相对湿度φ：相对湿度定义为给定的湿空气中水蒸气的摩尔分数与在同样温度t 和同样大气压力下饱和湿空气中水蒸气的摩尔分数的比值。
通常用百分数表示。
对于理想气体，相对湿度φ可以解释为：satw w satw w P P x x ,,==φ (9-1)Where w x - the mole fraction of the water vapor in moist air; 这里：w x -湿空气中水蒸气的摩尔分数；sat w x ,- mole fraction of water vapor in a saturated moist air at the same temperature; satw x ,-在同样温度下饱和湿空气中水蒸气的摩尔分数；w P - partial pressure of water vapor in moist air; w P -湿空气中水蒸气分压力 -sat w P ,saturation pressure of pure water at the same temperature, as shown in Tab.9-2.Note: The data of saturation pressure, specific volume and latent heat of evaporation are fromexperiments. The data of enthalpy are from calculation, and the zero value of the enthalpy is set for the saturated liquid water at 0C 0.注解：饱和压力，比容和潜热的数据是由试验得到。
焓值由计算得到，零值取为0C 0时的饱和液体的焓值。
(5) Degree of Saturation μ:Degree of saturation is defined as the ratio of the humidity ratio of moist air w to the humidity ratio of saturated moist air sat w at the same temperature and atmosheric pressure.(5) 饱和度μ:饱和度定义为在相同温度和大气压力下湿空气含湿量w 与饱和湿空气的含湿量sat w 之比。
wsat w satP B P B w w --⨯==,φμ (9-2)The difference between relative humidity φ and degree of saturation μ is usually less than 2%. 相对湿度φ与饱和度μ的差值通常小于2%。
(6) Humidity ratio (Moisture Content)w :The humidity ratio is the mass kg of water vapor interspersed in each kg of dry air. It should be noted that the mass of water refers only to the moisture in actual vapor state, and not to any moisture in the liquid state, such as dew, frost, fog or rain. The humididy ratio, like other several properties to be studied- enthalpy and specific volume-is based on 1kg of dry air.(6) 含湿量 (水分)w :含湿量是1kg 干空气当中水蒸气的质量含量。
需要注意的是水的含量只是以实际蒸气存在的湿气，而不包括以液态存在的湿气，如露水，霜，雾和雨。
和其它要学习的参数(如焓，比容)一样，含湿量也是基于一千克干空气所说。
)()(air dry of kg m vapor water of kg m w a w ⋅⋅⋅⋅⋅⋅=(9-3)In most applications of air conditioning and food refrigeration, both dry air and water vapor in moist air may be assumed as perfect gases. Dry air is assumed to be a perfect gas because its temperature is quite high relative to its saturation temperature, and water vapor is assumed to be a perfect gas because its pressure is quite low relative to its saturation pressure.[1] Therefore, we have在大多数空调和食品冷藏的应用中，干空气和湿空气中的水蒸气都被认为是理想气体。