Experimental and computational investigation of laser beam propagation through a free shear layer

Abstract

Experimental Shack–Hartmann Wavefront Sensor (SHWFS) measurements were collected and examined to further understand image-plane irradiance pattern behavior in the presence of potentially sharp thermodynamic gradients. An analysis of path-integrated phase and image-plane irradiance pattern spreading discovered regions within a weakly compressible shear layer where sharp gradients were previously not observed. This paper describes the analysis process and shows results which suggest that Shack-Hartmann wavefront sensors are not adequately resolving sharp thermodynamic gradients in aberrating flows.