Refrigerants commonly used refrigerants methane series, ethane series, propane series, cyclic organic compounds, zeotropic blends, azeotropic blends and organic compounds. Usually, a fluid, used in a heat pump and refrigeration cycle that can extract heat from another body or substance. Natural refrigerants sustainable ozone and climatefriendly alternatives to hcfcs introduction dr. The most reliable way to be safe is to choose a refrigerant that is neither toxic nor flammable. A comparison between refrigerants used in air conditioning. This tool can be used to determine individual state points by a graphical. Refrigerants thermodynamic, physical, chemical, safe ty related and environmental properties have been presented and discussed in the first part of the paper. The refrigerants have a thermodynamic property chart on pressureenthalpy coordinates with an abbreviated set of tabular data for saturated liquid and vapor on the faci ng page. Abstract models commonly used to calculate the thermodynamic properties of refrigerants are summarized. Dupont isceon mo79 r422a saturation propertiestemperature table. This article describes thermodynamic properties of the refrigerants the ideal refrigerant. For thermodynamics and fluid mechanics problems, values of entropy, specific heat energy etc must be known for various fluids and their value can easily be obtained from these tables.
Refrigerants are widely used in refrigeration cycle where cooling effect below the atmospheric temperatures are needed. The current refrigerant r4a has a global warming potential gwp of 0 with respect to co2. Refrigerants and their application presented by thomas e. These tables are based on experimental data from the database at the national institute of standards and technology nist. This section presents data for the thermodynamic and transport properties of refrigerants, arranged for the occasional users. The refrigerants have a fullpage thermodynamic property chart on pressureenthalpy coordinates with tabular data for the. Physical properties chemical formula ccl2 f2 molecular mass 120. R12 dichlorodifluoromethane properties thermodynamic properties of saturated and superheated dichlorodifluoromethane cf 2 cl 2 specific volume, enthalpy and entropy. Thermodynamic properties for the alternative refrigerants.
It was chosen as the preferred equation of state because it provided the most accurate fit of the thermodynamic data over the entire range of temperatures and pressures presented in these tables. Fundamental equations of state for hydrofluorocarbon hfc refrigerants were developed due to several percents of uncertainty of the specific heat in the gaseous phase near saturation and completely different behavior of the third virial coefficient. Thermophysical properties of aqueous solutions used as. Refrigerant r4a properties thermodynamic properties of refrigerant r4a, also known as 1,1,1,2tetrafluoroethane, r4a, freon 4a, forane 4a, genetron 4a, florasol 4a, suva 4a or hfc4a and norflurane inn. R32 has a gwp about one third that of r410a, and it has excellent properties as a refrigerant. Mineral oil is not miscible with current hfcbased refrigerants 19. The simulator used an equation of state to predict the thermodynamic properties of the refrigerant mixtures. The thermodynamic properties are interrelated and mainly depend on normal boiling point, critical temperature, molecular weight and structure. The thermodynamic properties of refrigerants columbushoa. Characterize the heat transfer and thermodynamic properties and efficiency performance of new refrigerants and blends. The refrigerants have a thermodynamic property charge. Positively innovative refrigerants r32 daikin chemical europe.
Pdf thermodynamics properties table suddiyas nawaz. The data fit and calculation of constants for hfc4a were performed for chemours at the nist under the supervision. Here are some of the desirable properties of refrigerant explained in detail. Thermodynamic properties a quantity which is either an attribute of an entire system or is a function of position which is continuous and does not vary rapidly over microscopic distances, except possibly for abrupt. The refrigerant evaporates again and thus completes the circuit. Regulatory oversight on refrigerants such as cfc, hcfc, and other synthetic refrigerants, have refocused attention on ammonia to emerge as one of the widely used refrigerants that, when released to. Thermodynamics of the refrigeration cycle basic knowledge thermodynamics of the refrigeration cycle heat dissipation during condensation. In fact, from the thermodynamic or heatcarrying standpoint, differences among refrigerants with similar. The desired thermodynamic properties are a boiling point somewhat below the target temperature, a high heat of vaporization, a moderate density in liquid. It was chosen as the preferred equation of state because it provided the most accurate. Thermophysical properties of refrigerants t his chapter presents data for thermodynamic and transport properties of refrigerants, arra nged for the occasional user. It is odorless, nontoxic, nonflammable, nonexplosive and noncorrosive. Policylegislation on fgases and alternatives two environmental frameworks one goal the montreal protocol and the kyoto protocol. Engineering thermodynamics by israel urieli is licensed under a creative commons attributionnoncommercialshare alike 3.
Table a1 molar mass, gas constant, and criticalpoint properties table a2 idealgas specific heats of various common gases table a3 properties of common liquids, solids, and foods table a4 saturated watertemperature table table a5 saturated waterpressure table table a6 superheated water table a7 compressed liquid water table a8 saturated icewater vapor. In todays world, other properties of the refrigerant are more important. Thermodynamic properties of hydrofluoroolefin r1234yf and. An equation of state is a function that can correlate all the thermodynamic properties of a fluid in a consistent way. This information is based on values calculated using the nist refprop database mclinden, m. The refrigerants have a thermodynamic property chart on pressure most cfc. Chapter 20, thermophysical properties of refrigerants. Abstract this chapter presents data for the thermodynamic and transport properties of refrigerants. Refrigerants of thermodynamics property the r22 refrigerant which is used as an alternative to cfcincluded refrigerants, has got a low odp value and thus, its use is permitted until the year 2030.
Thermodynamic properties of duponttm freonr 22 refrigerant. Appendix a thermodynamic property tables general because of ammonias widespread use as a refrigerant, comprehensive tables of thermodynamic properties are frequently needed by refrigeration engineers. Technical information at22 thermodynamic properties of dupontz freon. Thermodynamic properties of refrigerants with low gwp. Refrigerants thermodynamic, physical, chemical, safety related and environmental properties have been presented and discussed in the first part of the paper. Refrigerant r4a thermodynamic properties eng units 2 equations the mbwr equation of state was used to calculate the tables of thermodynamic properties. The refrigerant in any refrigerator or air conditioner flows continuously through the vapor compression cycle, absorbing the heat in the evaporator and releasing it in the.
Download natural refrigerants overview brochurepdf. Spreadsheet calculations of thermodynamic properties. A number of materials have physical and thermodynamic properties suitable for their use as refrigerants. Pdf development of fundamental equations of state for. Properties of commonly used refrigerants a refrigerant is a substance or mixture. Enthalpy or heat of combustion is one of the important parameters in assessing. Standard thermodynamic properties of chemical substances this table gives the standard state chemical thermodynamic properties of about 2400 individual substances in the crystalline, l iquid, and gaseous states. Both types involve the use of refrigerant blends to achieve alternatives that will act very much like r502 in refrigeration.
The thermodynamic properties of the pure refrigerants studied in this work are described by the reference eos listed in table 3. There is currently serious consideration of replacing it with r744 carbon dioxide in refrigeration and heat pump applications, as well as automotive air conditionong systems. Thermodynamic properties of refrigerants using artificial. These physical properties of refrigerants help us select the proper refrigerant for the application as per our requirement. Table aesuperheated refrigerant 4a figure a14eph diagram for refrigerant 4a table a16eproperties of the atmosphere at high altitude table a17eidealgas properties of air table a18eidealgas properties of nitrogen, n 2 table a19eidealgas properties of oxygen, o 2 table a20eidealgas properties of carbon dioxide, co 2. Carbon dioxide is widely used as a refrigerant in mechanical systems refrigerant, marine services, hospitals, etc.
Here, after a selection of the most promising lowgwp refrigerants among all the potential candidates, an analysis of some of the thermodynamic properties of the selected fluids is performed with. For pure refrigerants, the virial, cubic, martinhou, benedictwebbrubin, and helmholtz nist equations of state and the extended corresponding states model are discussed. Spreadsheet calculations of thermodynamic properties larry caretto, david mcdaniel, tom mincer csu, northridgeus air force academycsu, northridge abstract a thermodynamic property calculation tool has been developed based on the excel spreadsheet program. As the refrigerant flows through the continuous vapor compression cycle it absorbs heat from a lowtemperature reservoir and deflects it into the atmosphere. Refrigerants studied in this work, sources of their pure fluid equations of state in the software refprop 9. Whenever we choose them for particular use properties of refrigerants also plays a vital role in economic and environmental friendly application. Nist thermodynamic and transport properties of refrigerants and refrigerant. A cyclic process can be represente d ver y clearl y in t he ts diagram.
Fortunately ammonia has been very thoroughly studied by thermodynamicists over the years and. In the last two centuries, human ingenuity made it possible to control fully. The flammability of a proposed new refrigerant is a major consideration in assessing its utility for a particular application. Comparison of environmental impacts and physical properties of refrigerants ko matsunaga executive summary even before the invention of refrigeration, people wanted to improve their life by using ice to provide cold drinks and preserve food. Most of the halogenated refrigerants meet these requirements.
Important properties of ammonia as refrigerants are as follows. Many different refrigerants have been used in the past and are in use today with good ability to transfer heat from one place to another. The use of natural refrigerants generally leads to lower operating costs. Influence of those properties, which is of the utmost significance on the vapor compression process effi.
For example, in the ann for refrigerant r4a, p 1 is the pressure, p 2 and p 3 the liquid and vapor density, p 4 and p 5 the liquid and vapor en the subscript i varies from 1 to n n best on each model. Safety is perhaps the most important single factor in the selection of a refrigerant. Volkmar hasse, gtz proklima, germany preface volkmar hasse, gtz proklima i. Co2 as an alternative refrigerant and secondary fluid. Thermodynamic properties of duponttm freonr 12 r12. Thermodynamic properties of r4a tetraflouroethane cf3ch2f. A refrigerant is a substance or mixture, usually a fluid, used in a heat pump and refrigeration. Different refrigerants are used for different temperature conditions and there is no ideal one that is suitable for all conditions. Thermodynamics tutorial 5 heat pumps and refrigeration on completion of this tutorial you should be able to do the following. Thermodynamic properties of duponttm isceonr mo79 r. As a result, a refrigerant that has similar thermodynamic properties could be an alternative to r22. Volume internal energy enthalpy entropy degc mpa m3kg kjkg kjkg kjkgk temp.
The refrigerant in any refrigerator or air conditioner flows continuously through the vapor compression cycle, absorbing the heat in the evaporator and releasing it in the condenser. The paper on refrigerants has been divided in two parts. Fellow ashrae mcquay international staunton, virginia usa 1 what is a refrigerant. Refrigerants environmental properties physical and environmental properties of some common refrigerants refrigerants temperature and pressure charts temperature and pressure chart for refrigerants r22, r410a, r12, r4a, r401a, r409a, r502, r404a, r507a, r408a and r402a. Review of thermodynamic properties of refrigerants. Hydrofluorocarbon hfc refrigerants are possible alternatives to replace ozonedepleting chlorofluorocarbon and hydrochlorofluorocarbon hcfc refrigerants. In addition, we define two dimensionless distances from the critical point tt. The miscibility and better transport of oil through components of the air conditioning system, back to the compressor, are achieved by synthetic lubricants, such as pag polyalkylene glycol and poe polyol ester 19.
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