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Thermodynamic Properties of Molecular Oxygen

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Thermodynamic Properties of Molecular Oxygen NATIONAL BUREAU OF STANDARDS REPORT 2611 THERMODYNAMIC PROPERTIES OF MOLECULAR OXYGEN tv Harold ¥, Woolley Themodynamics Section Division of Heat and Power U. S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS U. S. DEPARTMENT OF COMMERCE Sinclair Weeks, Secretary NATIONAL BUREAU OF STANDARDS A. V. Astin, Director THE NATIONAL BUREAU OF STANDARDS The scope of activities of the National Bureau of Standards is suggested in the following listing of the divisions and sections engaged in technical work. In general, each section is engaged in special- ized research, development, and engineering in the field indicated by its title. A brief description of the activities, and of the resultant reports and publications, appears on the inside of the back cover of this report. Electricity. Resistance Measurements. Inductance and Capacitance. Electrical Instruments. Magnetic Measurements. Applied Electricity. Electrochemistry. Optics and Metrology. Photometry and Colorimetry. Optical Instruments. Photographic Technology. Length. Gage. Heat and Power. Temperature Measurements. Thermodynamics. Cryogenics. Engines and Lubrication. Engine Fuels. Cryogenic Engineering. Atomic and Radiation Physics. Spectroscopy. Radiometry. Mass Spectrometry. Solid State Physics. Electron Physics. Atomic Physics. Neutron Measurements. Infrared Spectroscopy. Nuclear Physics. Radioactivity. X-Rays. Betatron. Nucleonic Instrumentation. Radio- logical Equipment. Atomic Energy Commission Instruments Branch. Chemistry. Organic Coatings. Surface Cheipistry. Organic Chemistry. Analytical Chemistry. Inorganic Chemistry. Electrodeposition. Gas Chemistry. Physical Chemistry. Thermo- chemistry. Spectrochemistry. Pure Substances. Mechanics. Sound. Mechanical Instruments. Aerodynamics. Engineering Mechanics. Hy- draulics. Mass. Capacity, Density, and Fluid Meters. Organic and Fibrous Materials. Rubber. Textiles. Paper. Leather. Testing and Specifi- cations. Polymer Structure. Organic Plastics. Dental Research. Metallurgy. Thermal Metallurgy. Chemical Metallurgy. Mechanical Metallurgy. Corrosion. Mineral Products. Porcelain and Pottery. Glass. Refractories. Enameled Metals. Con- creting Materials. Constitution and Microstructure. Chemistry of Mineral Products. Building Technology. Structural Engineering. Fire Protection. Heating and Air Condition- ing. Floor, Roof, and Wall Coverings. Codes and Specifications. Applied Mathematics. Numerical Analysis. Computation. Statistical Engineering. Machine Development. Electronics. Engineering Electronics. Electron Tubes. Electronic Computers. Electronic Instrumentation. Radio Propagation. Upper Atmosphere Research. Ionospheric Research. Regular Propaga- tion Services. Frequency Utilization Research. Tropospheric Propagation Research. High Frequency Standards. Microwave Standards. Ordnance Development. These three divisions are engaged in a broad program of research Electromechanical Ordnance, and development in advanced ordnance. Activities include Ordnance Electronics. basic and applied research, engineering, pilot production, field testing, and evaluation of a wide variety of ordnance materiel. Special skills and facilities of other NBS divisions also contribute to this program. The activity is sponsored by the Department of Defense. Missile Development. Missile research and development: engineering, dynamics, intelligence, instrumentation, evaluation. Combustion in jet engines. These activities are sponsored by the Department of Defense. • Office of Basic Instrumentation • Office of Weights and Measures. NATIONAL BUREAU OF STANDARDS REPORT NBS NBS PROJECT 0302-50-2606 June 30, 1953 2611 THERMODYNAMIC PROPERTIES OF MOLECULAR OXYGEN Harold VI, Woolley Thermodynamics Section Division of Heat and Power Sponsored in part by Rational Advisory Committee for Aeronautics Order No. W-5594 Approved for public release by the In part, Is prohibited The publlcatloni t National Institute of Director of the tandards, Washington unleti permission Standards and Technology (NIST) has been specifically 25. D.C. Such 2015 port for Its own use. prepared f that on October 9, 1 FOREWORD This is one of a series of reports on the thermodynamic properties of gases compiled at the National Bureau of Standards at the suggestion and with the cooperation of the National Advisory Committee for Aero- nautics. Advances in methods of propulsion and the high speeds attain- ed thereby have emphasized the importance of accurate data on thermal properties of wind-tunnel and jet-engine gases. It has been the purpose of the project on thermal properties of gases to make a critical com- pilation of existing published and unpublished data, and to present such data in convenient form for application. The dimensionless char- acter of the tables and their general format should facilitate calcula- tions in aerodynamics, heat-transfer, and jet-engine problems. The work was conducted under the supervision of Fir. Joseph Hilsenrath by members of the Thermodynamics Section, Division of Heat and Power. C. W. Beckett, Chief Thermodynamics Section ^ UJiLteY) R. E. Wilson, Acting Chief Division of Heat and Power ii TAELS OF CONTENTS Page Foreword , . ii Table of Contents iii Summary 1 I Introduction 3 II SytbolS 6 III The experimental data of state for oxygen 11 IV Comparison of derived quantities with the experimental data , 13 V The calculation of the tables IS VI Conclusion 19 VII References 20 Figure 1 - FVT data for oxygen 23 Figure 2 - Heat of vaporization of liquid oxygen 24 Table 9*01 - Entropy of oxygen vapor at boiling point .••••••••«.«••• 25 Appendices Table 9*10 Specific heat enthalpy and entropy of molecular o:ygen in the ideal gas state. Table 9.11 Free energy of molecular oxygen in the ideal gas state. Table 10.10 Specific ' eat, nthalpy, and entropy of e’xraic oxygen in the ideal gas state. Table 10.11 Free energy of atomic oxygen in the ideal gas state. Table 9 .IS Density of ’r.olecular oxygen. Table 9*20 Compressibility factor for molecular oxygen. Table 9.22 Enthalpy and entropy of molecular oxygen. Table 9*24 Specific heat of molecular oxygen. Table 9.26 Specific heat ratio jf molecular oxygen. Table 9*32 Sound velocity in molecular oxygen. Table 9.39 Viscosity of oxygen. Table 9*42 Thermal conductivity of oxygen. Table 9*44 Prandtl number of oxygen. Table 9.50 Vapor pressure of oxygen. Table 1,30 Conversion factors. Temperature interconversion table. iii - i , , . SUMMARY The tables of thermal properties of molecular oxygen prepared for the NBS-NACA series are grouped together here for convenience in use. These tables include thermodynamic functions for the gas, both real and in the hypothetical ideal gas state, the transport properties of the gas, and the vapor pressure of the liquid. The ideal gas properties are given in tables 9*10 and 9.11. These include specific heat at constant pressure, enthalpy, entropy and the free energy function. For possible use with them, tables 10,10 and 10.11, giving the same properties for atomic oxygen, are also included. The real gas thermodynamic properties for molecular oxygen are given in tables 9. IS to 9.32 and include density, the compressibility factor or PV/RT, entropy, enthalpy, specific heat at constant pressure, the ratio of specific heats or Cp/C and v , the velocity of sound at very low frequency. For tables 9.1S to 9.32, the tabular entries correspond to pressures of 0.01, .1, .4, .7, 1, 4, 7, 10, 40, 70 and 100 atmospheres. The temperature range covered is from 100°K or slightly higher, up to 3000°K. The method of correlation of the PVT data allows the calculation of approximate values for temperatures much higher than used in obtaining the experimental data. This is due to the determination of a reasonable representation of interaction energies between molecules, based on an over-all fitting of the available data. -1- K The vapor pressure for liquid oxygen is given in table 9*50 "with values at every 5 degrees from 55° K to 150°K for rapid use for these temperatures or "when rough interpolated values are adequate. In a second part of the table, values of log^o? are tabulated more closely with uniformly spaced values of l/T, permitting very accurate inter- polation. The viscosity, thermal conductivity and Prandtl number are given in tables 9»39, 9*42, and 9*44 respectively. The viscosity is tabulated for atmospheric pressure over the temperature range 100° to 2000°K using the treatment of Hirschfelder, Bird and Spotz [17] for the Lennard-Jones 6-12 potential with the parameters s/k = 100 °K b cm^ mole"^chosen to the and Q ® 54.1 fit experimental data approxi- mately over their entire range. The thermal conductivity was calcu- lated from a purely empirical equation fitted to the experimental data, and the Prandtl number was computed in a straight-forward manner from these and the specific heat values. • 2 < I INTRODUCTION This set of mutually consistent tables of thermodynamic prop- erties of gaseous oxygen has been computed with the data of state represented by a pressure series xdiose temperature dependent co- efficients and their derivatives were used to calculate the derived thermodynamic properties. As the experimental PVT data are more abundant than other relevant data, cover a wider range of tempera- ture and pressure^ and are usually dependable, the equation of state forms an appropriate starting point for the calculation of the entire field of thermodynamic properties. In the representation of the PVT data for the NBS-NACA Tables, the objective was taken of covering adequately the limited range
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