用于宽聚焦激光 - 等离子体相互作用的超音速喷嘴的设计与表征

Design and characterization of supersonic nozzles for wide focus laser-plasma interactions.

作者信息

Lemos N, Lopes N, Dias J M, Viola F

机构信息

GoLP/Instituto de Plasmas e Fusão Nuclear, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.

出版信息

Rev Sci Instrum. 2009 Oct;80(10):103301. doi: 10.1063/1.3233895.

DOI:10.1063/1.3233895

PMID:19895054

Abstract

In this work we optimize the contour of supersonic nozzles to produce long and stable gas jets suitable to be used in loose focus laser-plasma applications. The nozzle design method takes into account the inclusion of a boundary layer that increases the length of the usable gas jet. Two 8 mm supersonic nozzles were characterized, one with a Mach number of 3 and another with a Mach number of 6, using a Mach-Zehnder interferometer performed with a He:Ne 4 cm expanded laser beam. The experimental results confirm that the inclusion of the boundary layer produces an 8 mm constant longitudinal density profile for the nozzle with a Mach number of 6 (NM6) and a 4.5 mm constant longitudinal density profile for the nozzle with a Mach number of 3 (NM3).

摘要

在这项工作中，我们优化了超音速喷嘴的轮廓，以产生适用于散焦激光等离子体应用的长且稳定的气体射流。喷嘴设计方法考虑了包含一个边界层，该边界层增加了可用气体射流的长度。使用马赫 - 曾德尔干涉仪，用氦氖4厘米扩展激光束对两个8毫米的超音速喷嘴进行了表征，一个喷嘴的马赫数为3，另一个喷嘴的马赫数为6。实验结果证实，对于马赫数为6的喷嘴（NM6），包含边界层会产生8毫米的恒定纵向密度分布；对于马赫数为3的喷嘴（NM3），会产生4.5毫米的恒定纵向密度分布。