REFRIGERANTS HFC-134a - AllChemi

1 Technical InformationT- 134a SIfThermodynamicPropertiesofHFC- 134a (1,1 ,1,2-tetrafluoroethane)Du Pont Product Names:SUVA 134a RefrigerantFORMACEL Z-4 Blowing AgentDYMEL 134a Aerosol PropellantDYMEL 134a /P Aerosol Propellant(Pharmaceutical Grade) DUPONTSUVAREFRIGERANTS1 Thermodynamic Properties of HFC- 134a refrigerant (1,1,1,2-tetrafluoroethane)SI UnitsNew tables of the thermodynamic properties of HFC-134ahave been developed and are presented here. These tablesare based on experimental data from the database at theNational Institute of Standards and Technology (NIST).Equations have been developed, based on the ModifiedBenedict-Webb-Rubin (MBWR) equation of state, whichrepresent the data with accuracy and consistency through-out the entire range of temperature, pressure, and PropertiesChemical FormulaCH2 FCF3 Molecular Point atOne Atmosphere C( F)Critical C( F) K( R)Critical kPa (abs)( psia)Critical kg/m3( lb/ft3)Critical m3/kg( ft3/lb)Units and Factorst = temperature in CT = temperature in K = C + = pressure in kiloPascals absolute [kPa (abs)]

2 ]vf= volume of saturated liquid in m3/kgvg= volume of saturated vapor in m3/kgV = volume of superheated vapor in m3/kgdf= 1/vf = density of saturated liquid in kg/m3dg= 1/vg = density of saturated vapor in kg/m3hf= enthalpy of saturated liquid in kJ/kghfg= enthalpy of vaporization in kJ/kghg= enthalpy of saturated vapor in kJ/kgH = enthalpy of superheated vapor in kJ/kgsf= entropy of saturated liquid in kJ/(kg) (K)sg= entropy of saturated vapor in kJ/(kg) (K)S = entropy of superheated vapor in kJ/(kg) (K)Cp= heat capacity at constant pressure in kJ/(kg) ( C)Cv= heat capacity at constant volume in kJ/(kg) ( C)vs= velocity of sound in m/secThe gas constant, R = J/(mole) (K)for HFC- 134a , R = kJ/kg KOne atmosphere = kPaReference point for enthalpy and entropy:hf = 200 kJ/kg at 0 Csf = 1 kJ/kg K at 0 CEquationsThe Modified Benedict-Webb-Rubin (MBWR) equation ofstate was used to calculate the tables of thermodynamicproperties.

3 It was chosen as the preferred equation of statebecause it provided the most accurate fit of the thermo-dynamic data over the entire range of temperatures andpressures presented in these tables. The data fit and calcu-lation of constants for HFC- 134a were performed forDu Pont at the National Institute of Standards and Tech-nology (NIST) under the supervision of Dr. Mark constants were calculated in SI units. For conversionof thermodynamic properties to Engineering (I/P) units,properties must be calculated in SI units and converted toI/P units. Conversion factors are provided for each propertyderived from the MBWR equation of Equation of State (MBWR) = an/Vn + exp ( Vc2/V2) an/V2n 17where the temperature dependence of the coefficients isgiven by:a1= RTa2= b1T + + b3 + b4/T + b5/T2a3= b6T + b7 + b8/T + b9/T2a4= b10T + b11 + b12/Ta5= b13a6= b14/T + b15/T2a7= b16/Ta8= b17/T + b18/T2a9= b19/T2a10= b20/T2 + b21/T3a11= b22/T2 + b23/T4a12= b24/T2 + b25/T3a13= b26/T2 + b27/T4a14= b28/T2 + b29/T3a15= b30/T2 + b31/T3 + b32/T4where T is in K = C + , V is in liters/mole(= m3/kg MW), Vc = liters/mole, P is in kPa,and R = bar (absolute) liters/mole coefficients for HFC- 134a .

4 B1= 523 5227 E 02b2= 375 1817 E+00b3= 178 8409 E+02b4= 316 8845 E+04b5= 261 3296 E+06b6= 377 6190 E 04b7= 419 4543 E+00b8= 525 3680 E+03b9= 220 3182 E+05b10= 451 9115 E 04b11= 451 0013 E 01b12= 016 8246 E+02b13= 404 7742 E 02b14= 183 5971 E+00b15= 316 3961 E+02b16= 165 1521 E 01b17= 436 8796 E 02b18= 423 3787 E+00b19= 176 6113 E 02b20= 850 2898 E+05b21= 479 9101 E+07b22= 521 9382 E+04b23= 473 5899 E+09b24= 220 0070 E+02b25= 245 0399 E+05b26= 919 6293 E+00b27= 893 2204 E+05b28= 632 1392 E 02b29= 516 8842 E+01b30= 904 2297 E 04b31= 619 2849 E 01b32= 958 3743 E+00 Ideal Gas Heat Capacity Equation (at constantpressure):Cp (J/mole K) = cp1 + cp2 T + cp3 T2cp1 = E+01 cp3 = E 04cp2 = E 01R = J/mole KMW = calculated in SI units from the equation andconstants listed above can be converted to I/P unitsusing the conversion factors shown below.

5 Please notethat in converting enthalpy and entropy from SI to I/Punits, a change in reference states must be included(from H = 200 and S = 1 at 0 C for SI units to H = 0and S = 0 at 40 C for I/P units). In the conversionequation below, H (ref) and S (ref) are the saturatedliquid enthalpy and entropy at 40 C. For HFC- 134a ,H (ref) = kJ/kg and S (ref) = kJ/kg (psia)= P (kPa) ( F)= (T[ C] ) + 32D (lb/ft3)= D (kg/m3) (ft3/lb)= V (m3/kg) (Btu/lb)= [H (kJ/kg) H (ref)] (Btu/lb R)= [S (kJ/kg K) S (ref)] (Btu/lb F) = Cp (kJ/kg K) (Btu/lb F) = Cv (kJ/kg K) (ft/sec)= vs (m/sec) Martin-Hou Equation of State (fit from MBWR data)As previously stated, the thermodynamic propertiespresented in these tables are based on the MBWR equation of state.

6 Coefficients for the Martin-Houequation of state are presented below for the conve-nience of those who may have existing computerprograms based on this equation of state. While not asaccurate as the data from the MBWR equation of state,particularly in the superheated region, data calculatedusing these Martin-Hou coefficients should be suffi-cient for most engineering = RT/(V b) + (Ai + BiT + Ci exp ( kT/Tc))/(V b) iFor SI unitsT and Tc are in K = C + , V is in m3/kg,and P is in kPaR = kJ/kg Kb, Ai, Bi, Ci, k are constants:A2= E 02A4= E 05B2= E 05B4= E 08C2= E+00C4= E 04A3= E 03A5= E 08B3= E 06B5= E 10C3= E 02C5= E 06b = E 04k = Vapor Pressurelog10 Psat = A + B/T + C log10 T + D T +E ([F T]/T) log10 (F T)For SI unitsT is in K = C + and P is in kPaA, B, C, D, E, F are constants.

7 A = E+01D = E 03B = E+03E= E 01C = E+01F= E+02 For I/P unitsT is in R = F + and P is in psiaA, B, C, D, E, F are constants:A = E+01D = E 03B = E+03E= E 01C = E+01F= E+024. Density of the Saturated Liquiddf = Af + Bf (1 Tr) (1/3) + Cf (1 Tr) (2/3) + Df (1 Tr)+ Ef (1 Tr) (4/3)For SI unitsTr = T/Tc, both in K = C + and df isin kg/m3Af, Bf, Cf, Df, Ef are constants:Af= E+02Df= E+02Bf= E+02Ef= E+02Cf= E+03 For I/P unitsTr = T/Tc, both in R = F + and df is in lb/ft3Af, Bf, Cf, Df, Ef are constants:Af= E+01Df= E+01Bf= E+01Ef= E+01Cf= E+01 For I/P unitsT and Tc are in R = F + , V is in ft3/lb,and P is in psiaR = (psia)(ft3)/lb Rb, Ai, Bi, Ci, k are constants.

8 A2= E+00A4= E 01B2= E 04B4= E 04C2= E+01C4= E+00A3= E 01A5= E 02B3= E 04B5= E 05C3= E+01C5= E 01b = E 03k = E+00 Ideal Gas Heat Capacity (at constant volume):Cv = a + bT + cT2 + dT3 + f/T2 For SI unitsCv = kJ/kg KT is in K = C + , b, c, d, f are constants:a = E+00d= E 08b = E 02f= E+04c = E 05 For I/P unitsCv = Btu/lb RT is in R = F + , b, c, d, f are constants:a = E 01d= E 09b = E 03f= E+04c = E 06ooo4 TABLE 1 HFC 134a Saturation Properties Temperature Table (continued)LIQUIDvfVAPORvgLIQUID1/vfVAPO R1/vgLIQUIDhfLATENThfgLIQUIDsfVAPORsgENT ROPYkJ/(kg)(K)VAPORhgPRESSUREkPa (abs)TEMP. CTEMP. CVOLUMEm3/kgDENSITYkg/m3 ENTHALPYkJ/kg 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 TABLE 15 LIQUIDvfVAPORvgLIQUID1/vfVAPOR1/vgLIQUID hfLATENThfgLIQUIDsfVAPORsgENTROPYkJ/(kg) (K)VAPORhgPRESSUREkPa (abs)TEMP.

9 CTEMP. CVOLUMEm3/kgDENSITYkg/m3 ENTHALPYkJ/kgTABLE 1 HFC 134a Saturation Properties Temperature Table (continued) 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 HFC 134a Saturation Properties Temperature Table (continued)LIQUIDvfVAPORvgLIQUID1/vfVAPO R1/vgLIQUIDhfLATENThfgLIQUIDsfVAPORsgENT ROPYkJ/(kg)(K)VAPORhgPRESSUREkPa (abs)TEMP. CTEMP. CVOLUMEm3/kgDENSITYkg/m3 (continued)7 LIQUIDvfVAPORvgLIQUID1/vfVAPOR1/vgLIQUID hfLATENThfgLIQUIDsfVAPORsgENTROPYkJ/(kg) (K)VAPORhgPRESSUREkPa (abs)TEMP. CTEMP. CVOLUMEm3/kgDENSITYkg/m3 ENTHALPYkJ/kgTABLE 1 HFC 134a Saturation Properties Temperature Table (continued) CVHSCpCp/CvvsVHSCpCp/Cvvs C8 TABLE 2 (continued)HFC- 134a Superheated Vapor Constant Pressure TablesTEMPTEMP CVHSCpCp/CvvsVHSCpCp/Cvvs CV = Volume in m3/kgH = Enthalpy in kJ/kgS = Entropy in kJ/(kg)(K)vs = Velocity of Sound in m/secCp = Heat Capacity at Constant Pressure in kJ/(kg)( C)Cp/Cv = Heat Capacity Ratio (Dimensionless)PRESSURE = kPa (abs)PRESSURE = kPa (abs) SAT SAT 65 60 55 50 45 40 35 30 25 20 15 10 45 40 35 30 25 20 15 10 = kPa (abs)PRESSURE = kPa (abs)

10 TABLE 2 TEMPTEMP CVHSCpCp/CvvsVHSCpCp/Cvvs CTEMPTEMP CVHSCpCp/CvvsVHSCpCp/Cvvs C9 TABLE 2 (continued)HFC- 134a Superheated Vapor Constant Pressure TablesV = Volume in m3/kgH = Enthalpy in kJ/kgS = Entropy in kJ/(kg)(K)vs = Velocity of Sound in m/secCp = Heat Capacity at Constant Pressure in kJ/(kg)( C)Cp/Cv = Heat Capacity Ratio (Dimensionless) 40 35 30 25 20 15 10 30 25 20 15 10 = kPa (abs)PRESSURE = kPa (abs)PRESSURE = kPa (abs)PRESSURE = kPa (abs)TEMPTEMP CVHSCpCp/CvvsVHSCpCp/Cvvs C10 TABLE 2 (continued)HFC- 134a Superheated Vapor Constant Pressure TablesTEMPTEMP CVHSCpCp/CvvsVHSCpCp/Cvvs CV = Volume in m3/kgH = Enthalpy in kJ/kgS = Entropy in kJ/(kg)(K)vs = Velocity of Sound in m/secCp = Heat Capacity at Constant Pressure in kJ/(kg)( C)Cp/Cv = Heat Capacity Ratio (Dimensionless) 25 20 15 10 25 20 15 10 = kPa (abs)PRESSURE = kPa (abs)PRESSURE = kPa (abs)PRESSURE = kPa (abs)TEMPTEMP CVHSCpCp/CvvsVHSCpCp/Cvvs CTEMPTEMP CVHSCpCp/CvvsVHSCpCp/Cvvs C11 TABLE 2 (continued)HFC- 134a Superheated Vapor Constant Pressure TablesV = Volume in m3/kgH = Enthalpy in kJ/kgS = Entropy in kJ/(kg)(K)