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Equation of State of Fluid NH3 from P-V-T and Ultrasound Measurements to 12 Kbar
1983 MRS Meeting (1983)
  • R. L. Mills, Los Alamos National Laboratory
  • D. H. Lienbenberg, Los Alamos National Laboratory
  • Richard Alan Lesar, Los Alamos National Laboratory
  • PH. Pruzan
A piston-cylinder apparatus was used to measure the pressure, volume, temperature, and ultrasonic velocity (P,V,T,u) of fluid NH3 from 195 to 320 K at pressures up to 12 kbar. Over 1200 sets of P-V-T-u and P-V-T data were fitted to a Tait-type equation of state (EOS) by non-linear least-squares minimization. With quadratic terms in T for the two fitted parameters, the rms deviation is ± 0.2% in V and ± 0.9% in u, which is comparable to the experimental error. The simple Tait EOS is useful over the entire fluid range between the vaporization and melting curves up to T exceeding room temperature. Measurements of u and calculations of the constant-pressure heat capacity Cp show regular behavior, differing noticeably from values given by a 44-parameter EOS recently published by NBS. It is concluded that incorporating u in the formulation of an EOS improves its self consistency markedly.
Publication Date
This conference proceeding is from MRS Proceedings 22 (1983): 43, doi:10.1557/PROC-22-43. Posted with permission.
Citation Information
R. L. Mills, D. H. Lienbenberg, Richard Alan Lesar and PH. Pruzan. "Equation of State of Fluid NH3 from P-V-T and Ultrasound Measurements to 12 Kbar" 1983 MRS Meeting (1983)
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