Laser-induced shock waves in liquids

Abstract

High-speed schlieren photography of the interaction of a TEA CO2 laser pulse with the surface of absorbing liquids shows the formation of a complex shock structure in the liquid. The shock structure in liquids with different absorption coefficients at 10.6 μm is compared. In carbon tetrachloride a cylindrical wave is generated in the bulk of the liquid in addition to the hemispherical wave which is formed at the liquid surface. The cylindrical wave leads the hemispherical one, and this separation is interpreted as differential attenuation in the initial phase. This implies a shock velocity above the sound speed within the first 0.5 μs.