Hfc4a tetrafluoroethane is made by process of twostep gasphase fluoridation between trichloroethylene pce and hydrofluoric acid hf. Thermodynamic properties of hfc 4a free pdf ebooks. These tables are based on experimental data from the database at the national institute of standards and technology nist. 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 table a21eidealgas properties of carbon monoxide, co table a22eidealgas properties of hydrogen, h 2 table a23eidealgas properties of. This study is part of an international project coordinated by the subcommittee on transport properties. So that these blends may be recommended as dropin ods substitutes. It has long been used in a variety of airconditioning and refrigeration applications in a variety of markets. Refrigerants physical properties engineering toolbox. For reducing the weight of heat exchangers, most of the. Hfc4a, coupled with its low toxicity, make it a very efficient and safe replacement refrigerant for.
Thermodynamic properties of hfc4a refrigerant 1,1,1,2tetrafluoroethane engineering ip units equations the modified benedictwebbrubin mbwr equation of state was used to calculate the tables of thermodynamic properties. Key word halogenated ethane hcfc123 hcfc141b hfc4a thermal conductivity transient hotwire method. Difficult to ignite hfo1234yf due to high minimum ignition energy. The transition from hfc 4a to a lowgwp refrigerant in. The enthalpy and entropy values of saturated liquid are set to zero at. Pdf refrigerant types, issues, trends and future options. Honeywell is a longtime supplier of propellants and solvents to the aerosol industry. These include a line of hfcbased solvents the genesolv s series and genetron 4a, an hfc propellant. Material safety data sheet freon 4a auto version 3. It is not the type of refrigerant used in most cars today. R4a belongs to a group of chemicals called hydrofluorocarbons hfcs and is also known as hfc4a.
However, most of the heat transfer and flow performances are still not very clear uptodate. A thermodynamic property model explicit in the helmholtz energy is. Thermodynamic properties of rl34a l,1,1,2tetrafluoroethane 1 marcia l. Acute inhalation exposures at very high concentrations of hfc4a have shown central nervous system depression in laboratory animals. Pdf thermodynamic analysis and effects of replacing hfc. Most pre1994 model year vehicles used cfc12 also called r12.
The data were analyzed to obtain correlations in terms of density and pressure. Stable in normal condition, hfc4a is odorless, colorless, noncorrosive. Abstract the thermodynamic surlace of r4a is expressed in terms a 32term modified benedict. Spauschus georgia technical research institute, atlanta, ga 30332, usa in response to international protocol agreements and national regulatory actions promoted by the increasing concern for ozone depletion and the greenhouse effect, hfc 4a has emerged as a leading candidate for cfc 12 substitution in automotive air conditioners. However, mixing hfc 4a with flammable gasses or liquids can result in a flammable 4a should never be mixed with any flammable gas or liquid.
New correlations for the thermodynamics properties of r4a are presented. The refrigerant used in mobile air conditioning systems. Cfc 12 had a proven, outstanding record of product safety over many years in various applications, such as domestic, commercial. Hfc4a is not a low pressure refrigerant and thus not a drop in replacement candidate for cfc11.
Thermodynamic properties of r4a 1,1,1,2tetrafluoroethane. We dont know when or if this item will be back in stock. Hfc 4a refrigerant is non flammable and non explosive. When pressurised with air or oxygen, the mixture may become flammable. Saturated refrigerant4atemperature table concluded.
It was chosen as the preferred equation of state because it provided the most accurate fit of the thermo dynamic data over the entire range of temperatures and pressures presented in these tables. Kyle, chemical and process thermodynamics englewood cliffs, nj. It is based on the most accurate measurements of pressure. The experiments were performed at temperatures from 2 to 293 k at pressures up to 20 mpa. Greenhouse gases with high global warming potential highgwp gases are hydrofluorocarbons hfcs, perfluorocarbons pfcs, and sulfur hexafluoride sf 6, which together represented 3 percent of u.
R4a has a global warming potential gwp of 0 with respect to carbon dioxide. Evaluation of hfc245ca for commercial use in low pressure. Hfc4a chargecheck refrigerant charging cylinder 16oz, with case, thermal engineering u7002 currently unavailable. Cardiac arrhythmias were seen in dogs exposed to 80,000 ppm hfc4a for 5 minutes, when followed by an injection of epinephrine. Isothermal properties isobaric properties isochoric properties saturation properties temperature increments saturation properties pressure increments. Measurements of the thermodynamic properties of hfo1234yf were conducted. J639, j2844, j1739 hfo1234yf is a climatefriendly refrigerant. Thermodynamic cycle analysis of mobile air conditioning.
Theoretical exergy analysis of hfo1234yf and hfo1234ze. Modeling of thermodynamic properties for pure refrigerants and. Hfc4a is the most common mvac refrigerant used since the 1990s. Thermodynamic properties of hfc4a the chemours company reference point for enthalpy and entropy. Modeling of state and thermodynamic cycle properties of hfo1234yf using a cubic equation of state. Modeling of state and thermodynamic cycle properties of. It was chosen as the preferred equation of state because it provided the most accurate fit of the thermo. Toxicity of hfc 4a today hfc 4a 1,1,1,2 tetrafluoroethane is widely used, having been introduced as a replacement for cfc 12. Although hfc4a does not deplete the ozone layer, it is a potent greenhouse gas with a high global warming potential. Thermophysical properties of hfc143a and hfc152a final report 1 april 1993 30 june 1994 w. Wagnera new form of the equation of state for pure substances and its application to oxygen. A fundamental equation of state for the helmholtz free energy of r 4a 1,1,1,2. The properties of ice are based on hyland and wexler, formulations for the thermodynamic properties of the saturated phases of.
Moreover, hfo1234yf has similar thermodynamic properties to hfc4a, which makes it a good candidate for replacing the hfc4a. The retrofitting of hfc4a system by dropin of hfor1234yf is expected to give the lesser cooling capacity by 8% with the lower co. Study of r161 refrigerant as an alternate refrigerant to. Fukushimasaturated liquid densities of hcfc123, hfc4a, cfc11 and cfc12. Certain mixtures of hcfcs or hfcs with chlorine may become flammable or reactive under certain conditions.
The refrigerant r502 then facing a fate of complete phase out and thus the performance were compared with r404a, a main alternate refrigerant to. Read effective potentials for liquid simulation of the alternative refrigerants hfc4a cf 3 ch 2 f and hfc125 cf 3 chf 2, fluid phase equilibria on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. At present, it can be considered that the ester type is superior overall. International standard formulation for the thermodynamic properties of 1,1,1,2tetrafluoroethane hfc4a for temperatures from 170 k to 455 k and pressures up to 70 mpa, j.
Haynes thermophysics division national institute of standards and technology 325 broadway boulder, colorado 80303 july 1994 prepared for the airconditioning and refrigeration technology institute under arti mclr project number 65050800. The data fit and calculation of constants for hfc4a were performed for chemours at the nist under the supervision. A thermodynamic property model for the r4a245fa mixtures. Heat transfer coefficient and pressure drop for forced. 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. Table 7 properties of the various refrigerating oils for hfc4a p hfc4a stability cfc12 oidation mutual high temperaure. The equation is found to represent the experimental results with average deviations of 2. The effect of liquid inundation, vapor shear, and noncondensible gases on the condensation of refrigerants hfc4a and hcfc123 a dissertation submitted to the. The physical properties of hfc4a in comparison to cfc12 are presented in table 1. Measurement and formulation of the thermodynamic properties of. The thermodynamic and physical properties of hfc4a, coupled with its low toxicity, make it a very efficient and safe replacement refrigerant for cfc12 in many segments of the refrigeration industry, most notably in automotive air conditioning.
Mclinden thermophysics division national institute of standards and technology boulder, co 803033328 u. The effect of liquid inundation, vapor shear, and non. Please select the desired standard state convention. Recently, a new refrigerant, hfo1234yf has been developed with similar thermodynamic properties to hfc4a but much lower gwp value gwp equals to 4 in comparing to 1430 of hfc4a. The study on the replacement of high gwp refrigerant such as hfc4a is an important and urgent issue in the coming years. You should use the term refrigerant not the brand name when. This phenomenon is referred to as cardiac sensitization and is an.
The properties of the various oils in coparison ith mineral oil are shown in table 7. Thermodynamic properties of hfc4a 1, 1, 1, 2tetrafluoroethane na on. Depletion potential odp and vapor pressure and other properties similar to those of hfc4a 1,1,1,2tetrafluoroethane. For full table with specific volume, heat content enthalpy liquid and vapor rotate the screen. An equation of state formulation of the thermodynamic properties of. The thermal conductivity of hfc 4a was measured in the liquid phase with the polarized transient hotwire technique. Refrigerant types, issues, trends and future options. Hfc4a chargecheck refrigerant charging cylinder 16oz. Thermodynamic properties of r4a tetraflouroethane cf3ch2f. This information is based on values calculated using the nist refprop database mclinden, m.
Thermal conductivity of halogenated ethanes, hfc4a. Hydrofluorocarbons are used mainly as residential and automotive refrigerants. Hfc4a because of its environmental friendly properties with introducing ihx. Hydrofluorocarbon hfc 4a or 1,1,1,2tetrafluoroethane is a gaseous halocarbon that is being considered as a prime candidate for replacing other halocarbon materials, such as freon 12 dichlorodifluoromethane and freon 22, for use in air conditioning. Vehicle manufacturers have used two different refrigerants in automotive ac systems. This is a haloalkane refrigerant with thermodynamic properties similar to r12 dichlorodifluoromethane but with insignificant ozone depletion. Hfc4a compressor systems, many polar compounds have been synthesized and evaluated such. The transition from hfc 4a to a lowgwp refrigerant in mobile air conditioners hfo1234yf.
The data fit and calculation of constants for hfc4a were performed for du pont at the national institute of standards and tech. 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. State and thermodynamic cycle property data were presented for the new refrigerant hfo1234yf. It is expected as a good candidate of replacing the refrigerant hfc4a. At pressures below the triplepoint pressure of 518kpa, carbon dioxide exists as a solid or gas. Hfc4a was developed to replace chlorofluorocarbon cfc refrigerants that contain chlorine, which damages the ozone layer.
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