Solkane 410 Thermodynamics

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1 SOLVAY FLUOR SOLKANE - INFORMATION SERVICE Solkane 410 Thermodynamics SOLVAY FLUOR Technical Service - Refrigerants - Product Bulletin no.: T/09.04/04/E P.O. Box 0 Phone +49/511/ Hannover Fax +49/511/ Hans-Boeckler-Allee 0 refrigerants@solvay.com Hannover / Germany Internet:

2 CONTENTS 1 UNITS AND SYMBOLS... 3 INTRODUCTION THERMOPHYSICAL PROPERTIES PHYSICAL DATA BASIS OF THERMODYNAMIC CALCULATION TRANSPORT PROPERTIES Dynamic Viscosity of Saturated Liquid Dynamic Viscosity of Saturated and Superheated Vapour Thermal Conductivity of Saturated Liquid Thermal Conductivity of Saturated Vapour Surface Tension Specific Heat Capacity of Saturated Liquid COMPATIBILITY OF MATERIALS ELASTOMERES THERMOPLASTICS METALS REFRIGERANT OILS FLAMMABILITY TOXICITY VAPOUR TABLE, WET VAPOUR RANGE SOLKANE VAPOUR TABLE, SUPERHEATED RANGE SOLKANE SFD-AK T/09.04/04/E

3 1 Units and Symbols Symbol Unit Meaning/Definition A, B [-] Parameters of the Wagner equation C [-] Parameter of the equation for density of boiling liquid D [kj/(kg K)] Parameter of the equation for specific heat capacity in an ideal gas state E, F, G [-] Parameter of the Martin-Hou equation H [Pa s/k] Parameter of the equation for dynamic viscosity of vapour J [W/(m K)] Parameter of the equation for thermal conductivity of the saturated liquid K [W/(m K)] Parameter of the equation for thermal conductivity of the saturated vapour L [N/(m K)] Parameter of the equation for surface tension M [kj/(kg K)] Parameter of the equation for specific heat capacity of the saturated liquid R [bar m 3 /(kg K)] Gas constant T [K] Temperature b [m 3 /kg)] Parameter of the Martin-Hou equation c [kj/(kg K)] Specific heat capacity e [kj/kg] Specific exergy h [kj/kg] Specific enthalpy k [-] Parameter of the Martin-Hou equation p [bar] Pressure r [kj/kg] Enthalpy of vaporization s [kj/(kg K)] Specific entropy t [ C] Temperature v [m 3 /kg] Specific volume η [Pa s] Dynamic viscosity λ [W/(m K)] Thermal conductivity ρ [kg/m 3 ] Density σ [N/m] Surface tension SFD-AK T/09.04/04/E 3

4 Indices Liquid Vapour c Critical value r Reduced value i Run index u Ambient conditions p Isobar v Isochor 0 Ideal gas SFD-AK T/09.04/04/E 4

5 Introduction The refrigerant Solkane 410 is a long-term replacement for applications, where a compact design and a high energy efficiency shall be realised. Solkane 410 replaces R and also R13B1. The ozone depletion potential of the hydrochlorofluorocarbon (HCFC) R is reduced to a fraction of the ODPs of chlorofluorocarbons (CFCs). R is therefore regarded as an intermediate solution. The use of HCFCs will be gradually reduced and these products will finally be banned. By 030 the production of HCFCs will be phased out in developed countries 1. Accelerated phase out scenarios may apply in selected countries especially in Europe. Solkane 410 is a near azeotropic blend of R3 and R15 (50 /50 weight-%). Both components are partly halogenated hydrofluorocarbons, containing only carbon, fluorine and hydrogen. They do not contribute to the depletion of the stratospheric ozone layer. Due to the minimal temperature glide (<0.K) Solkane 410 can be treated as a pure fluid for technical applications. Compared to R Solkane 410 has a significant higher volumetric capacity. Solkane 410 is non-flammable. Its toxicity is low and comparable to the toxicity of R. The pressure level of Solkane 410 higher is than that of R. Solkane 410 is therefore unsuitable for the retrofit of existing R-units. R13B1-units can be adapted to the use with Solkane In the sence of Montreal Protocol (1995 Vienna meeting) SFD-AK T/09.04/04/E 5

6 3 Thermophysical Properties 3.1 Physical Data Chemical name [-] Difluoromethane/ Pentafluoroethane/ Chemical formula [-] CH F /CF 3 CHF CAS No. [-] / Molecular weight [kg/kmol] 7.6 Boiling point [ C] Critical temperature [ C] 70. Critical pressure [bar] 47.7 Saturated liquid density [kg/m 3 ] 1061 Saturated vapour density [kg/m 3 ] Vapour pressure [bar] Enthalpy of vaporization 1 [kj/kg] Liquid thermal conductivity [W/m K] 87.49E-3 Vapour thermal conductivity [W/m K] 16.53E-3 Surface tension of liquid [N/m] 5.158E-3 Specific heat capacity of liquid [kj/(kg K)] 1.69 Specific heat capacity of vapour 1 [kj/(kg K)] Liquid viscosity [Pa s] 0.117E-3 Flammability limit in air 3 [Vol.-%] None 3 1 at bar at 5 o C and saturated conditions 3 according to DIN and UL 18 SFD-AK T/09.04/04/E 6

7 3. Basis of Thermodynamic Calculation The thermodynamic calculation equations have been adapted to ISO/DIS 17584, as at 1/003. They fulfil this standard with the exception of the thermal capacities in a saturated state of 0.59 < T R < 0.94 and in an overheated state of 0.5MPa < p < 0.5MPa and T max = 440K. The Wagner equation B B B3 B4 ( A1 ( 1 TR ) + A ( 1 TR ) A3 ( TR ) A4 ( TR ) A5 ( TR ) A ) TR ln = + (1) pr 6 T p where TR = and pr = Tc pc was chosen to describe the vapour pressure. The constants and values for the critical pressure pc and the critical pressure T c are as follows: Bubble Pressure Dew Pressure A 1 [-] A [-] A 3 [-] A 4 [-] A 5 [-] A 6 [-] B 1 [-] B [-] B 3 [-].5.5 B 4 [-] 3 3 T c [K] p c [bar] A slight difference between dew- and vapour pressure for Solkane 410 do exists. The difference is smaller than 0.0 bar and is therefore classified as insignificant for technical purposes. The density of the boiling liquid is described by the equation ( ) ( ) ( ) ( ) ρ R = 1+ C1 1 T R + C 1 T R + C 1 T R + C 1 T 3 R () ρ where ρ = R. ρc The constants and the value for the critical density are: C 1 [-] C 4 [-] C [-] ρ c [kg/m 3 ] C 3 [-] SFD-AK T/09.04/04/E 7

8 The specific heat capacity under ideal gas conditions is represented by the equation 3 = D + D T + D T + D T D T (3) c 0 + p The coefficients are: D 1 [kj/(kg K)] E-01 D 4 [kj/(kg K 3 )] E-09 D [kj/(kg K )] E-03 D 5 [kj/kg] E+01 D 3 [kj/kg] E-06 The equation of state according to Martin-Hou is p = RT z E F1T + G1e z ktr E + + FT + Ge 3 z ktr E + z 3 4 E F4T + G4e 5 z and is a good representation of the pvt relationship for Solkane 410. The coefficients of the equation are: ktr (4) E 1 [-] E-03 F [-] E-10 E [-].1593E-07 F 4 [-] E-14 E 3 [-] E-10 G 1 [-] E-0 E 4 [-] E-11 G [-] E-06 F 1 [-] 3.638E-06 G 4 [-] 1.31E-09 b [m 3 /kg] E-04 k [-] R [bar m 3 /(kgk)] E-03 with z = v b. The equation for specific heat capacity under ideal gas conditions (3) and the thermal equation of state (4) form the basis of the specific enthalpy and entropy calculation. the equation for the specific enthalpy and entropy is transformed into h = h 0 + e + -k TR ( pv - RT ) T + D1T + D G G R z z + D 1 4 ( 1+ k T ) + + G 4z 3 4 T D 4 E lnt + z 1 E + z E + 3z 3 3 E + 4z 4 4 (5) and zp1 T s = s0 + R ln + D1 lnt + DT + D3 RT F1 F F4 k -k T G1 G R e z z 4z T z z with z = v b and p 1 =1,013bar. c D4 T G4 4 4z (6) SFD-AK T/09.04/04/E 8

9 The Clausius - Clapeyron equation was used to generate thermodynamic data in the wet vapour range. dp dt 1 h''- h' = T v''- v' (7) Rearranging equation (7) gives dp h'= h''- dt T v''- v ( ' ) The intergration constants h 0 und s 0 are found by letting (8) h (t = 0 C)= 00.0 kj/kg s (t = 0 C)= kj/(kg K) to be h 0 = kj/kg s 0 = kj/(kg K) If neither the kinetic nor the potential energies are taken into account, the specific exergy may be found by the following equation: ( ) e= h h T s s u u u where the subscript u indicates ambient conditions. The saturation pressure of the substance at T u = 90 K serves as the reference pressure. Applying the preconditions mentioned above, the constants h u and s u are found to be as follows: h u = 6.04 kj/kg s u = kj/(kg K), for which specific exergy is set to e = 0 according to existing agreements. (9) SFD-AK T/09.04/04/E 9

10 3.3 Transport Properties Dynamic Viscosity of Saturated Liquid The viscosity of the saturated liquid of Solkane 410 was measured within the temperature range of -50 to 60 C. The following regression equation is valid for the liquid phase: η ln 10 3 = H 0 + H1t + H t + H 3 t 3 (10) with t in C and η in 10-3 Pa s. The coefficients are: H 0 = [Pa s] H = e -5 [Pa s/k ] H 1 = [Pa s/k] H 3 = e -7 [Pa s/k 3 ] Saturated liquid viscosity η in 10-3 Pa s 0,4 0,3 0, 0, Temperature t in C Figure 1: Dynamic viscosity of the saturated liquid SFD-AK T/09.04/04/E 10

11 3.3. Dynamic Viscosity of Saturated and Superheated Vapour The viscosity of the saturated and superheated vapour of Solkane 410 was measured in a temperature range of -50 to 50 C. The data can be represented by the following equations η = η 0 + η (11) with η0 = ( MT ) σ Ω η 1 T *, * kt T = ε and Ω * * * * 3 * 4 ( T ) = exp[ (ln( T ) (lnT ) (lnT ) (lnT ) ] η = T p V. R c c z c = and RTc ρr 0 Tc 1 [ ln( ρ )] e 1 ( F z ζ ) R0 0 ρ R0 ρc c (1 a-c) ρ ρ = and F = 1 for Solkane 410 as a light polar agent. (1 d-f) In equation (1) the constants are as follows. R the universal gas constant = 8314 [J kmol -1 K -1 ] ρ c the critical density = [kg/m 3 ] ρ 0 the density at 1.013bar and [kg/m 3 ] temperature as defined by T T c the critical temperature = [K] The constants of equation (11) where determined to be ζ = [1/(Pa s)] σ = [nm] ε/k = [K] SFD-AK T/09.04/04/E 11

12 Saturated vapor viscosity η'' in 10-6 Pa s Temperature t in C Figure : Dynamic viscosity of saturated vapour SFD-AK T/09.04/04/E 1

13 3.3.3 Thermal Conductivity of Saturated Liquid The thermal conductivity of saturated liquid can be expressed with the regression equation λ = J t (13) J where t is in C and λ in 10-3 W/(mK). The coefficients of the equation are: J 0 = [10-3 W/(mK)] J 1 = [10-3 W/(mK )] Thermal conductivity of saturated liquid λ in 10-3 W/(m K) Temperature t in C Figure 3: Thermal conductivity of saturated liquid SFD-AK T/09.04/04/E 13

14 3.3.4 Thermal Conductivity of Saturated Vapour The thermal conductivity of saturated vapour can be expressed using the regression equation λ = K + (14) K1t + Kt + K3t K4t where t is in C and λ in 10-3 W/(m K). The coefficients of the equation are as follows: K 0 = [10-3 W/(mK)] K 3 = e -6 [10-3 W/(m K 4 )] K 1 = [10-3 W/(mK ] K 4 = e- 8 [10-3 W/(m K 5 )] K = e -3 [10-3 W/(mK 3 )] Thermal conductivity of saturated vapour λ in 10-3 W/(mK) Temperature t in C Figure 4: Thermal conductivity of saturated vapour SFD-AK T/09.04/04/E 14

15 3.3.5 Surface Tension The surface tension of the liquid can be expressed using the regression equation σ = L + (15) L1t + Lt L3t where t is in C and σ in 10-3 N/m. The coefficients of the equation are: L 0 = [10-3 N/m] L =.1740e -4 [10-3 N/(mK )] L 1 = [10-3 N/(mK)] L 3 =.1147e -6 [10-3 N/(mK 3 )] Surface tension σ in 10-3 N/m Temperature t in C Figure 5: Surface tension SFD-AK T/09.04/04/E 15

16 3.3.6 Specific Heat Capacity of Saturated Liquid The specific heat capacity of saturated liquid can be expressed using the equation p ( T ) 1 + M ( 1 T ) + M ( 1 T ) 3 + M ( T ) 6 9 c = M + M (16) R R 3 R 4 1 R where T follows: R T =, c p T c is in kj/(kg K) and T is in K. The coefficients of the equation are as M 0 = [kj/(kgk)] M 3 = [kj/(kgk)] M 1 = [kj/(kgk)] M 4 = [kj/(kgk)] M = [kj/(kgk)] Specific heat capacity of saturated liquid cp in kj/(kgk) 4,5 4 3,5 3,5 1,5 1 0, Temperature t in C Figure 6: Specific heat capacity of saturated liquid SFD-AK T/09.04/04/E 16

17 4 Compatibility of Materials 4.1 Elastomeres The compatibility of the elastomeres that are normally used in refrigeration systems with Solkane 410 is generally good. Cold extraction tests that where carried out on CR (chlorbutadiene rubber or Neoprene ), NBR (acrylonitrilebutadienerubber) and HNBR (hydrated acrylnitrilbutadiene rubber) showed only slight swelling and yielded negligible amounts of extract. Fluorinated rubbers (FKM and FPM) are not recommended because of their considerable swelling and blistering when used with Solkane 410 or with other HFC refrigerants. Ethylenepropylenediene rubber is only to be recommended where the presence of mineral oil in the refrigeration cycle can be excluded. The effect of the lubricant that is used must not be ignored. Recommendations made by the lubricant and compressor manufacturers must be followed. 4. Thermoplastics Experience with CFC and HCFC has shown that only a limited number of plastics are resistant to fluorinated refrigerants. Polytetrafluoroethylene, polyacetale and polyamide might be taken into account for the use with Solkane 410. It is again vital to take the effect of the lubricant into account. 4.3 Metals Solkane 410 is generally used in conjunction with lubricants (Ester oils, PAG-oils) in refrigeration technology. In combination both materials are compatible with the metals and alloys usually found in machines and apparatus. Only zinc, magnesium, lead and aluminium alloys with more than % magnesium by mass should be avoided. The water content of refrigeration oil depending on oil type should especially be taken into account. Values of not more than 50 ppm are to be aimed at. SFD-AK T/09.04/04/E 17

18 5 Refrigerant Oils Like all fluorinated hydrocarbons, Solkane 410 is immiscible with mineral oils. Ester oils (POE) are normally used as lubricants. The solubility of these oils in Solkane 410 is a function of temperature and composition. The following diagrams show the solubility properties of various lubricants with Solkane 410. Highly viscous lubricants tend to give large miscibility gaps. The precise miscibility gaps of the individual oils can be obtained from the lubricant manufacturers. Miscibility gap Ester oil A Oil concentration in the refrigerant Figure 7: Miscibility behaviour of Solkane 410 and ester oil A SFD-AK T/09.04/04/E 18

19 Miscibility gap Ester oil B Oil concentration in the refrigerant Figure 8: Miscibility behaviour of Solkane 410 and ester oil B Miscibility gaps Ester oil C + D Oil concentration in the refrigerant Figure 9: Miscibility behaviour of Solkane 410 and ester oil C SFD-AK T/09.04/04/E 19

20 6 Flammability R3 as a pure component is flammable, whereas R15 is not. According to DIN and UL 18 Solkane 410 is not flammable. 7 Toxicity The toxicity of R3 and R15 was extensively tested within the scope of the PAFT programme (Programme for Alternative Fluorocarbon Toxicity Testing). PAFT recommended an occupational exposure limit of 1000 ppm for both products. The toxicity of Solkane 410 can therefore be regarded as low and comparable to the toxicity of R. SFD-AK T/09.04/04/E 0

21 8 Vapour Table, Wet Vapour Range Solkane 410 t p p v v ρ ' ρ h h r s s [ C] [bar] [bar] [dm 3 /kg] [dm 3 /kg] [kg/dm 3 ] [kg/m 3 ] [kj/kg] [kj/kg] [kj/kg] [kj/kg K] [kj/kg K] SFD-AK T/09.04/04/E 1

22 Vapour Table, Wet Vapour Range Solkane 410 t p p v v ρ ' ρ h h r s s [ C] [bar] [bar] [dm 3 /kg] [dm 3 /kg] [kg/dm 3 ] [kg/m 3 ] [kj/kg] [kj/kg] [kj/kg] [kj/kg K] [kj/kg K] SFD-AK T/09.04/04/E

23 Vapour Table, Wet Vapour Range Solkane 410 t p p v v ρ ' ρ h h r s s [ C] [bar] [bar] [dm 3 /kg] [dm 3 /kg] [kg/dm 3 ] [kg/m 3 ] [kj/kg] [kj/kg] [kj/kg] [kj/kg K] [kj/kg K] SFD-AK T/09.04/04/E 3

24 Vapour Table, Wet Vapour Range Solkane 410 t p p v v ρ ' ρ h h r s s [ C] [bar] [bar] [dm 3 /kg] [dm 3 /kg] [kg/dm 3 ] [kg/m 3 ] [kj/kg] [kj/kg] [kj/kg] [kj/kg K] [kj/kg K] SFD-AK T/09.04/04/E 4

25 9 Vapour Table, Superheated Range Solkane bar C 0.5 bar C 0.7 bar C 0.99 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar C 0.58 bar C 0.81 bar C 1.10 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar C 0.65 bar C 0.89 bar C 1.1 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk SFD-AK T/09.04/04/E 5

26 Vapour Table, Superheated Range Solkane bar C 1.76 bar C.9 bar C.93 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar C 1.9 bar C.49 bar C 3.17 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar C.10 bar C.70 bar C 3.43 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk SFD-AK T/09.04/04/E 6

27 Vapour Table, Superheated Range Solkane bar -.00 C 4.63 bar C 5.7 bar C 7.00 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar C 4.98 bar C 6.13 bar C 7.47 bar -.00 C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg KJ/kgK bar C 5.34 bar C 6.55 bar C 7.97 bar 0.00 C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk SFD-AK T/09.04/04/E 7

28 Vapour Table, Superheated Range Solkane bar.00 C 10.0 bar 8.00 C 1.15 bar C bar 0.00 C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg KJ/kgK C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar 4.00 C 10.8 bar C 1.87 bar C bar.00 C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar 6.00 C bar 1.00 C bar C bar 4.00 C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk SFD-AK T/09.04/04/E 8

29 Vapour Table, Superheated Range Solkane bar 6.00 C bar 3.00 C.95 bar C 6.54 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar 8.00 C 0.78 bar C 4.10 bar C 7.8 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk bar C 1.85 bar C 5.9 bar 4.00 C 9.15 bar C t v h s t v h s t v h s t v h s C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk C dm 3 /kg kj/kg kj/kgk SFD-AK T/09.04/04/E 9

Solkane 134a Thermodynamics

SOLVAY FLUOR SOLKANE - INFORMATION SERVICE Solkane 134a Thermodynamics SOLVAY FLUOR Technical Service - Refrigerants - PRODUCT BULLETIN NO.: T/09.04/01/E P.O. Box 220 Phone +49/511/857-2653 30002 Hannover