THE EFFECT OF IMPURITIES DUE TO ABLATION ON THE ELECTRON NUMBER DENSITY OF AIR PLASMA

The results are given of calculations of the equilibrium composition i n N-O-K-Mo(W)-C-H systems at a pressure of 1 atm and temperature rangi ng from 1600 to 5600 K, characteristic of the conditions in the bounda ry layer near a body performing hypersonic motion in the atmosphere. T he effect of the concentration of impurities (C, H, K, W, Mo) on the e lectron number density in the air plasma is investigated. It is found that, up to a temperature of 3000 K for molybdenum and 3500 K for tung sten, the addition of metals (0.1-5%) leads to appreciable reduction o f the electron number density in mixtures of air with additives (C, H, K). In so doing, the carbon and hydrogen content in the system should not exceed 5%. These phenomena may affect the propagation of radiowav es in the plasma near the body. The problem of simulating the ablation of W and Mo during entry of the body into the atmosphere is discussed .