激光能量学实验室中超音速气体喷嘴预测性能模型的验证

Validation of predictive performance models for supersonic gas-jet nozzles at the Laboratory for Laser Energetics.

作者信息

McMillen K R, Heuer P V, Gjevre J M, Milder A L, Charles P, Filkins T, Rinderknecht H G, Froula D H, Shaw J L

机构信息

University of Rochester's Laboratory for Laser Energetics, Rochester, New York 14623, USA.

University of Alberta, Edmonton, Alberta T6G 2R3, Canada.

出版信息

Rev Sci Instrum. 2024 Jul 1;95(7). doi: 10.1063/5.0215756.

DOI:10.1063/5.0215756

PMID:39016699

Abstract

We present results characterizing the neutral-density distributions produced by the supersonic nozzles used in experiments on the OMEGA-60 and OMEGA-EP laser systems at the University of Rochester's Laboratory for Laser Energetics (LLE). Axisymmetric Fluent® simulations using LLE nozzle specifications capture the viscous effects, gas expansion, and shock waves that complicate flow predictions for offsets above the nozzle exit. These simulations show good agreement with neutral-density measurements obtained using a four-wave shearing interferometer. An analytical form is given for the plateau length. Fits to simulation data for boundary layer thickness, mean plateau density, and density ramps are given as functions of nozzle offset and nozzle backing pressure for a number of nozzles and gases.

摘要

我们展示了对罗切斯特大学激光能量学实验室（LLE）的OMEGA - 60和OMEGA - EP激光系统实验中使用的超音速喷嘴产生的中性密度分布进行表征的结果。使用LLE喷嘴规格进行的轴对称Fluent®模拟捕捉到了粘性效应、气体膨胀和冲击波，这些因素使喷嘴出口上方偏移处的流动预测变得复杂。这些模拟结果与使用四波剪切干涉仪获得的中性密度测量结果吻合良好。给出了平台长度的解析形式。针对多个喷嘴和气体，给出了边界层厚度、平均平台密度和密度梯度的模拟数据拟合，这些拟合是喷嘴偏移和喷嘴背压的函数。