Stochiometry Air − CH4 Mixture: Composition, Thermodynamic Propertiess and Transport Coefficients


  • A. Harry Solo Laplace, UMR 5213 CNRS-UPS-INP, Université Paul Sabatier 118 route de Narbonne, bat3R2, 31062 Toulouse Cedex
  • M. Benmouffok Laplace, UMR 5213 CNRS-UPS-INP, Université Paul Sabatier 118 route de Narbonne, bat3R2, 31062 Toulouse Cedex
  • P. Freton Laplace, UMR 5213 CNRS-UPS-INP, Université Paul Sabatier 118 route de Narbonne, bat3R2, 31062 Toulouse Cedex
  • J.-J. Gonzalez Laplace, UMR 5213 CNRS-UPS-INP, Université Paul Sabatier 118 route de Narbonne, bat3R2, 31062 Toulouse Cedex



air-CH4, plasma composition, constant pressure, constant mass density, thermodynamic properties, transport coefficients


This work is related to the determination of the local thermodynamic equilibrium (LTE) data of 90.5% air and 9.5% CH4 mixture. The results of chemical composition, thermodynamic properties and transport coefficients are presented for temperatures (300 K to 30 kK) and pressure (1 and 10 bars) or mass density (0.1481 and 1.111 kg.m−3). The chemical composition is determined using the mass action law. Input data come from the NIST and JANAF sites. For pressure equation, Debye-Huckel’s first order and virial’s second order corrections are used in the equation system to take into account the different particle interactions. For the considered mixture (90.5% air and 9.5% CH4) the properties are compared to those of pure air.


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