Degradation of the disperse component of the active medium of a pulsed chemical HF laser

Abstract

The Brownian coagulation model and the Stokes particle precipitation law were used to analyse the dynamics of changes in the characteristics of a condensed disperse component of the chemically active medium of a pulsed HF laser. It was found that, if coagulation predominates over precipitation, the required average particle size (r0 ∼ 0.1 — 0.5 μm) and concentration (N ∼ 5 × 108 — 107 cm-3) of an aluminium aerosol in an H2 — F2 — O2 — He chemically active medium can be reached in ∼ 1000 s. The precipitation of particles begins to compete with the coagulation only for r0 ≥ 1μm.