A hot channel model of a femtosecond laser pulse, characteristic of the FLEET (Femtosecond Electronic Excitation Tagging) diagnostic method, is used to explore the effect of localised thermal perturbations on laminar flow fields. Excellent agreement between the flow perturbations generated numerically and experimental measurements of the FLEET process are observed. The interaction of the generated shock waves and localised high temperature region with a laminar boundary layer and a laminar shear layer was simulated. No significant perturbations were observed in the boundary layer simulation however an artificial thickening of the shear layer was seen in the shear layer simulation. Differences in the temperature of the FLEET filaments, the hot channel geometry and the shear stress are suggested reasons why thickening is only observed in the shear layer simulations.
展开▼
