Experimental investigation on the effect of ionization seed mass fraction on gas plasma jet deflection

In order to study the effect of ionization seed mass fraction on gas plasma jet deflection, Cs₂CO₃ was selected as ionization seed, and the combustion temperature and conductivity in chemical equilibrium were calculated by Chemkin software. A calculation scheme for mixed combustion of methane with air and Cs₂CO₃ at initial temperature T₀ = 300 K and initial pressure p₀ = 1.04 × 10⁵ Pa is determined. The gas temperature and conductivity were calculated when the mass fraction of ionization seed was 1%, 5% and 10%, respectively. According to the calculation results, the quantitative relationship between conductivity and temperature was fitted. The results showed that the fifth-order polynomial had good fitting accuracy for three different seed mass fraction schemes, and high conductivity could be obtained by keeping the excess air coefficient near 0.9. The plasma jet deflection experiments under different working conditions were carried out on a thrust-vector test rig controlled by MHD. The effect of jet deflection is analyzed. The results showed that at the same temperature, the higher the mass fraction of ionization seed is, the higher the conductivity is, the greater the Lorentz force on the plasma is, and the larger the jet deflection angle is. The calculation results can provide theoretical basis for the corresponding experimental research.