FORECAST OF THE CHEMICAL AND TRANSPORT PROPERTIES OF A CARBON-OXYGEN PLASMA IN ISOCHORIC CONDITIONS

The composition and transport properties of CO₂, CO, CH₄, CO+Ar, CO+Fe have been calculated at constant volume. Except at low temperature ( T<3000 K ) with the formation of condensed species or more complex molecules, pressure increases with temperature at constant volume. For example for 1 mole of CH₄ starting at 0.1 MPa and 298K it can reach 35 MPa at 20000 K. The net result is a shift to higher temperature of dissociation and ionization. The electrical conductivity ae at constant volume increases drastically relatively to that obtained at 0.1 MPa over 15000 K, in spite of the decrease of the electron density n_?. This is due to the increase of neutral species n_i with a much lower electron-neutral species collision cross section σ_ei (σ_e is increased proportionaly to the inverse of n_i*σ_ei ) . The viscosity exhibits always a maximum when the ionization degree reaches 3% but this maximum is shifted to a higher temperature and its peak value is higher. The thermal conductivity peak due to dissociation is shifted to higher temperature and its value is reduced while the conductivity peak due to ionization, again being shifted to higher temperature, is increased in its value.