Initiation of combustion of titanium plates in an air stream by pulsed radiation

We have experimentally investigated the effect of the velocity of an air stream and the static pressure in the stream in the subsonic, near sonic, and supersonic flow regimes on the process of initiation of self-sustaining combustion of plates made from titanium alloy OT4-1V by pulsed laser radiation. We have established the existence of an upper limit for the flow velocity for initiation of combustion. We have shown that reduction of the static pressure below atmospheric leads to a sharp reduction of the range of flow velocities for which self sustaining combustion of the plates is initiated; and for p<0.6·10⁵ Pa, combustion does not develop over the entire range of M numbers from 0 to 2.5.Central Institute of Aerodynamics, 3 Zhukovskii 140160. Translated from Fizika Goreniya i Vzryva, Vol. 30, No. 2, pp. 46–51, March–April, 1994.