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Models for Viscosity, Thermal Conductivity, and Surface Tension of Selected Pure Fluids As Implemented in REFPROP V10.0

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Models for Viscosity, Thermal Conductivity, and Surface Tension of Selected Pure Fluids As Implemented in REFPROP V10.0 NISTIR 8209 Models for Viscosity, Thermal Conductivity, and Surface Tension of Selected Pure Fluids as Implemented in REFPROP v10.0 Marcia L. Huber This publication is available free of charge from: https://doi.org/10.6028/NIST.IR.8209 NISTIR 8209 Models for Viscosity, Thermal Conductivity, and Surface Tension of Selected Pure Fluids as Implemented in REFPROP v10.0 Marcia L. Huber Applied Chemicals and Materials Division Material Measurement Laboratory This publication is available free of charge from: https://doi.org/10.6028/NIST.IR.8209 August 2018 U.S. Department of Commerce Wilbur L. Ross, Jr., Secretary National Institute of Standards and Technology Walter Copan, NIST Director and Under Secretary of Commerce for Standards and Technology ______________________________________________________________________________________________________ Disclaimer Certain commercial entities, equipment, or materials may be identified in this document in order to describe an experimental procedure or concept adequately. Such identification is not intended to imply recommendation or endorsement by the National Institute of Standards and Technology, nor is it intended to imply that the entities, materials, or equipment are necessarily the best available for the purpose. This publication is available free of charge from: https://doi.org/10.6028/NIST.IR.8209 ______________________________________________________________________________________________________ Abstract We describe models for the viscosity, thermal conductivity, and surface tension for selected fluids implemented in version 10.0 of the NIST computer program, NIST Standard Reference Database 23, also known as NIST Reference Fluid Thermodynamic and Transport Properties Database (REFPROP). These fluids do not presently have published reference fluid quality models in the open literature, so we provide preliminary models based on available data as an interim measure This to allow calculations of these properties. Comparisons with available experimental data are given. publication Keywords natural gas; refrigerants; REFPROP; surface tension; thermal conductivity; viscosity. is available free of charge from: https://doi.org/10.6028/NIST.IR.8209 i ______________________________________________________________________________________________________ Table of Contents Abstract ............................................................................................................................................. i Keywords .......................................................................................................................................... i Table of Contents ............................................................................................................................. ii 1. Introduction ..................................................................................................................................... 1 This 2. Pure-Fluid Extended Corresponding States Viscosity Model .......................................................... 1 publication 3. Pure-Fluid Extended Corresponding States Thermal Conductivity Model ..................................... 3 4. Pure-Fluid Dedicated Polynomial Thermal Conductivity Model ..................................................... 4 5. Pure-Fluid Surface Tension Model .................................................................................................. 5 6. Application to Specific Fluids in REFPROP v10 ................................................................................. 6 is available 6.1. Alkanes ..................................................................................................................................... 7 6.1.1 n-pentane .................................................................................................................. 7 6.1.2 isopentane (2-methylbutane) .................................................................................... 9 6.1.3 neopentane (2,2-dimethylpropane) ........................................................................ 11 free 6.1.4 isohexane (2-methylpentane) .................................................................................. 13 of 6.1.5 3-methylpentane .................................................................................................... 16 charge 6.1.6 2,2-dimethylbutane (neohexane) ........................................................................... 21 6.1.7 2,3-dimethylbutane ................................................................................................ 26 6.1.8 isooctane (2,2,4-trimethylpentane) ........................................................................ 31 from: 6.1.9 n-docosane .............................................................................................................. 36 6.2. Alkenes and Dienes ................................................................................................................ 41 https://doi.org/10.6028/NIST.IR.8209 6.2.1 propylene ................................................................................................................ 41 6.2.2 isobutene ................................................................................................................. 42 6.2.3 trans-2-butene ......................................................................................................... 46 6.2.4 cis-2-butene ............................................................................................................. 48 6.2.5 1-butene .................................................................................................................. 50 6.2.6 1-pentene ................................................................................................................ 53 6.2.7 propadiene .............................................................................................................. 55 6.2.8 1,3-butadiene .......................................................................................................... 55 6.3. Alkynes ................................................................................................................................... 58 6.3.1 acetylene (ethyne) ................................................................................................... 58 6.3.2 propyne .................................................................................................................... 60 6.3.3 1-butyne ................................................................................................................... 62 6.4. Cycloalkanes and Cycloalkenes .............................................................................................. 63 6.4.1 cyclopropane............................................................................................................ 63 6.4.2 cyclopentane ............................................................................................................ 64 6.4.3 methylcyclohexane .................................................................................................. 66 6.4.4 propylcyclohexane ................................................................................................... 69 6.4.5 cyclobutene .............................................................................................................. 70 ii ______________________________________________________________________________________________________ 6.5. Ethers ..................................................................................................................................... 70 6.5.1 dimethyl ether ......................................................................................................... 70 6.5.2 diethyl ether ............................................................................................................. 73 6.6. Siloxanes................................................................................................................................. 77 6.6.1 hexamethyldisiloxane (MM) ................................................................................... 77 6.6.2 octamethyltrisiloxane (MDM) .................................................................................. 81 This 6.6.3 decamethyltetrasiloxane (MD2M) .......................................................................... 85 6.6.4 dodecamethylpentasiloxane (MD3M) .................................................................... 89 publication 6.6.5 tetradecamethylhexasiloxane (MD4M) ................................................................... 91 6.6.6 octamethylcyclotetrasiloxane (D4) ......................................................................... 92 6.6.7 decamethylcyclopentasiloxane (D5) ........................................................................ 96 6.6.8 dodecamethylcyclohexasiloxane (D6) .................................................................. 100 is 6.7. Fluorinated and Chlorinated Compounds, Refrigerants ...................................................... 102 available 6.7.1 R40 (methyl chloride) ............................................................................................ 102 6.7.2 R1140 (vinyl chloride) ............................................................................................ 103 6.7.3 R1123 (trifluoroethylene) ...................................................................................... 106 6.7.4 R143a (1,1,1-trifluoroethane) ..............................................................................
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