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arXiv · 2103.12408

Symmetric and asymmetric shocked gas jets for laser-plasma experiments

Lucas Rovige·Julius Huijts·Aline Vernier·Igor Andriyash·François Sylla·Vidmantas Tomkus·Valdas Girdauskas·Gediminas Raciukaitis·Juozas Dudutis·Valdemar Stankevic·Paulius Gecys·Jerome Faure
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Abstract

Shocks in supersonic flows offer both a high-density and sharp density gradients that can be used, for instance,for gradient injection in laser-plasma accelerators. We report on a parametric study of oblique shocks created by inserting a straight axisymmetric section at the end of a supersonic "de Laval" nozzle. The impact of different parameters such as throat diameter and straight section length is studied through computational fluid dynamics (CFD) simulations. Experimental characterizations of a shocked nozzle are compared to CFD simulations and found to be in good agreement. We then introduce a newly designed asymmetric shocked gas jet, where the straight section is only present on one lateral side of the nozzle, thus providing a gas profile that can be used for density transition injection. In this case, full-3D fluid simulations and experimental measurements are compared and show excellent agreement.

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Lucas Rovige, Julius Huijts, Aline Vernier, Igor Andriyash, François Sylla, Vidmantas Tomkus, Valdas Girdauskas, Gediminas Raciukaitis, Juozas Dudutis, Valdemar Stankevic, Paulius Gecys, Jerome Faure. 2021-03-23. Symmetric and asymmetric shocked gas jets for laser-plasma experiments. https://doi.org/10.1063/5.0051173

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