According to the montreal protocol, the odp of refrigerants should be zero, i. As a side effect, part of it is carried by the refrigerant and circulates through the entire cycle. A refrigerant with a lower boiling point tends to have a better ability to cool. Snap listed hfc152a as acceptable subject to use conditions for new vehicles only. The toxicity depends upon the concentration and exposure.
It is given by the mass of refrigerant emissions in kilograms times the gwp of the refrigerant leakage rate mass of refrigerant leaking from system x gwp of refrigerant typical leakage rates. Technical information at22 thermodynamic properties of dupontz freon. Refrigeration, air conditioning and heat pumps 5th edition. Xoj 9617 sltlvd l l09l seqjeselolt\\l phll l thermophysical properties of liquid secondary refrigerants. The flood of the airconditioner, that is, the refrigerants, their properties, merits and. Refrigerants are chemicals used for cooling in automobile air conditioners, window air conditioners.
Pdf thermodynamic properties of refrigerant r116 from. Desirable properties of refrigerants chemical engineering site. Their thermodynamic characteristics constitute as ideal replacement for r502 for refrigeration sector in new facilities at low and medium temperatures. The refrigerants should be non poisonous to humans and food stuff. A throttling valve should be used to control the flow of refrigerant to the suction side to ensure that a liquid. Freon refrigerants r11, r12, and r22, plus ammonia and water, will be discussed in terms of the abovementioned categories. Freon refrigerants r11, r12, and r22, plus ammonia and water, will be discussed in terms of. The ashrae refrigerant safety classification is a good indicator. These properties are pressure, temperature, volume, density, enthalpy, flammability, ability to mix with oil, moisture reaction, odor, toxicity, leakage tendency, and leakage detection. Refrigerant 744 carbon dioxide thermophysical properties of refrigerants. It is one of a series prepared to provide a record of the database entries in printed form.
This refrigerant is nontoxic, nonflammable and noncorrosive. Vapour charging solstice n40 may result in the wrong refrigerant composition and could damage the system. Special care has to be taken to the flammability of isobutane. Clear and comprehensive, it is suitable for both trainee and professional hvac engineers, with a straightforward approach that also helps inexperienced readers gain a comprehensive introduction to the fundamentals of the technology. In terms of its properties, it should be considered a highclass refrigerant. Toxicity is the important properties of refrigerants. The thermodynamic efficiency of a refrigeration system depends mainly on its operating temperatures. Table a10 properties of saturated refrigerant4a 879. Hfc152a is a climatefriendly refrigerant that may be pursued in the future. Refrigerants are widely used in refrigeration cycle where cooling effect below the. This technology has its challenges in all stages of its realization from the. A impact of refrigerant property uncertainties on prediction. Table 3 shows the tested material and the test conditions. Refrigerant properties motor vehicle air conditioning.
The refrigerant is a heat carrying medium which during their cycles i. With the discovery of the damaging effect of cfcs and hcfcs refrigerants to the ozone layer, the hfc family of refrigerant has been widely used as their replacement. Table a16 properties of gases at 1 atm pressure 885886. It has long been used in a variety of airconditioning and refrigeration applications in a variety of. Ammonia, r717, is an attractive refrigerant alternative. Classification can be divided into class 1, class 2, class 3.
Jul 17, 2017 a refrigerant with a lower boiling point tends to have a better ability to cool. Effects of refrigerant properties on refrigerant performance citeseerx. A refrigerant with a ozonedepletion potential odp damages the ozone layer, which is an entirely separate issue from climate change. The earliest mechanical refrigeration used air as a working fluid. Isobutane r 600a is a possible refrigerant for this application, with good energy efficiency, but with a very different characteristic in several points, which implies the design to be made or adopted for this refrigerant. So, a tradeoff has to be done in order to achieve as high a cop as possible. Properties of a good refrigerants mechanical engineering. Thermophysical properties of liquid secondary refrigerants.
It is essential that systems be charged with liquid from the cylinder. Characteristics of hfc refrigerants purdue university. Excellent lowgwp, highly energy efficient and nonflammable refrigerant for low and medium temperature in commercial refrigeration. Pdf properties of refrigerants from cubic equations of state. Jun 20, 2015 the refrigerant is a heat carrying medium which during their cycles i.
Starting a system with liquid refrigerant in the compressor. Refrigerants thermodynamic, physical, chemical, safe ty related and environmental properties have been presented and discussed in the first part of the paper. Pdf seminar is focused on the fundamentals of vapor compression. Zeotropic blend designed to serve as a replacement for r404a in supermarket refrigeration retrofits or new systems. The low moisture content enables the refrigerant to work more effectively and more importantly, have less corrosive impact on your refrigeration systems. Reference states used for most refr igerants correspo nd to the international convention of 200 kjkg for enthalpy and 1 kjkgk for entropy, both for saturated liquid at 0c. Control of liquid refrigerant floodback to the compressor during operation.
Refrigeration, air conditioning and heat pumps, fifth edition. Purpose the refrigerant database is an information system on alternative refrigerants, associated lubri. Solstice 1234ze r1234ze honeywells new solstice ze refrigerant hfo 1234ze is an energyefficient alternative to traditional refrigerants in aircooled and watercooled chillers for supermarkets and commercial buildings, as well as in other medium temperature applications such as heat pumps, refrigerators, vending machines and co2 cascade systems in commercial refrigeration. This report provides citations and summaries from the arti refrigerant database from the recently added and key citations file. However, important practical issues such as the system design, size, initial and operating costs, safety, reliability, and serviceability etc. Industrial refrigerants selection guide from stellar. In fact, at present the environment friendliness of the refrigerant is a major factor in deciding the usefulness of a particular refrigerant. Tables of the thermodynamic properties of dupont freon. Dec 26, 2015 refrigerant properties refrigerants can be characterized by a number of properties.
It has been used in refrigeration systems since 1840 and in vapor compression since 1860. A once widely used hcfc refrigerant is a synthetic compound called monochlorodifluoromethane, referred to in the industry as r22. In refrigeration systems, lubricant oil cannot be considered alone, because it functions as a refrigerantoil mixture. The important environmental and safety properties are.
It is nontoxic, with zero odp ozone depletion potential and very low gwp global warming potential. Answer a states that r4a changes from a vapor to a liquid as it absorbs heat. Jun 12, 2014 pros and cons of popular industrial refrigerants including ammonia, co2, hydrocarbons as r22 refrigerants are being phased out, many food processing facilities are reevaluating their industrial refrigerants due to environmental concerns, legislative requirements and cost efficiency. Pdf thermodynamic properties of refrigerant r116 from cubic. The thermodynamic properties are interrelated and mainly depend on normal boiling point, critical temperature, molecular weight and structure. Technical r404a data sheet features and uses of r404a r404a is a ternary mixture consisting of r125, r143a and r4a. Solstice 1234ze r1234ze honeywells new solstice ze refrigerant hfo 1234ze is an energyefficient alternative to traditional refrigerants in aircooled and watercooled chillers for supermarkets and commercial buildings, as well as in other medium temperature applications such as heat pumps, refrigerators, vending machines and co2 cascade systems in commercial. Refrigerant properties motor vehicle air conditioning mvac.
The txv metering device converts high pressure liquid into little low pressure liquid droplets that change from a liquid to a vapor. Standards and climate policy implications of engineering constraints hung pham, emerson climate technologies harvey sachs, american council for an energyefficient economy abstract there is no single perfect refrigerant for diverse air conditioning, refrigeration, and industrial applications. Pdf refrigerant types, issues, trends and future options. R404a is characterized by a remarkable chemical stability and low. Refrigerant properties refrigerants can be characterized by a number of properties. R407cpsltt r407cpsvtt r407c t sl p p r407c t s vp p r407cdsltt r407cdsvtt r407chsltt r407chsvtt r407cssltt r407cssvtt r407ccpsltt r407ccpsvtt r407ccvsltt r407ccvsvtt r407csurftenstt r407cwsltt r407cwsvtt. This reminds us of some of the basic characteristics of r4a refrigerant. There are several heat transfer loops in refrigeration system as described below. R1270 care 45 propylene r1270, also known as care 45, is refrigerant grade propylene propene, a natural, or not in kind, refrigerant suitable for use in low and medium temperature refrigeration applications. This makes the equipments compact and reduced the operating cost.
R407cpsltt r407cpsvtt r407c t sl p p r407c t s vp p r407cdsltt r407cdsvtt r407chsltt r407chsvtt r407cssltt r407cssvtt r407ccpsltt r407ccpsvtt. R4a is also known as tetrafluoroethane cf3ch2f from the family of hfc refrigerant. Refrigerants properties pdf product data summary and thermodynamic tables. Refrigerants with higher boiling points tend to be more efficient and may work well in a smaller machine.
This information is based on values calculated using the nist refprop database mclinden, m. Forane 4a, r4a, pressure temperature chart, pt chart, hvac, refrigeration, air conditioning, refrigerant gas created date. Thermodynamic properties of duponttm freonr 22 refrigerant. Apr 12, 2020 higher heat transfer coefficient requires smaller area and lower pressure drop. In most vapourcompression refrigeration systems, a certain amount of lubricant oil is used to lubricate moving parts. Table are based on 320 k for those whose critical reading and writing the lakota language pdf temperatures are. Introduction r744 is a high purity carbon dioxide co 2 based refrigerant gas with a typical moisture content less than 10 parts per million. Classification of refrigerants refrigerants are classified according to their way of absorption or extraction of heat from substances stored in the refrigerator. Pros and cons of popular industrial refrigerants including ammonia, co2, hydrocarbons as r22 refrigerants are being phased out, many food processing facilities are reevaluating their industrial refrigerants due to environmental concerns, legislative requirements and cost efficiency. Pdf thermodynamic properties were predicted, for saturated phases and in the singlephase region for refrigerant ri16 c2f6. R12 overview r12 is r4as older predecessor, and it was used in most automotive air conditioning systems, as well as in household refrigerators.
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