COMBINED EFFECT OF IMPURITIES OF WATER VAPORS, POTASSIUM AND FLUORINEON THE ELECTRON NUMBER DENSITY OF AIR PLASMA

Calculations are made of the equilibrium composition of air plasma wit h the impurities of 1) steam, 2) alkali metal (potassium) and an elect rophilic agent (fluorine), and 3) potassium, fluorine, and water vapor s for the conditions of ballistic experiments in the region of the rea r critical point behind a body (2000 K less than or equal to T less th an or equal to 5000 K, 0.01 less than or equal to p less than or equal to 1 atm) with the concentration of impurities in the air of up to 0. 5 mole fractions. The results of calculations made it possible to inve stigate a combined and separate effect of individual components on the electron number density. It is shown that what occurs during combined injection of water and fluorine-containing electrophilic substances i s not the summation of the effects of reduction (compared to pure air) of the electron number density, but rather their mutual compensation. This is the cause of the failure of experiments, in which no decline in the electron number density was observed during combined injection of water and SF6.