In this study, a two-dimensional fluid model is proposed to simulate the underwater discharge in a He/H 2 O-filled bubble at atmospheric pressure. The molar fraction of water vapor is varied in the range of 0.01%–1% to investigate the dependence of discharge dynamics and reaction products on water vapor concentration (WVC). The numerical results show that most properties of the discharge sensitively depend on the WVC. The increase of WVC leads to an increase in the electron density and discharge propagation velocity, which is attributed to Penning ionization between He* and H 2 O. The main positive ion switches from He + to H 2 O + , while the WVC increases from 0.01% to 1%. The dominant reactive oxygen species is OH, whose peak density is about two orders of magnitude higher than that of O. Besides, the densities of OH and O radicals increase with the increasing WVC. It is shown that the formation mechanism of O radicals is signific...

中文翻译：

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大气压力下水蒸气浓度对He / H 2 O填充气泡内水动力学和水下放电反应产物的影响

在这项研究中，提出了一个二维流体模型来模拟大气压下充有He / H 2 O的气泡中的水下排放。水蒸气的摩尔分数在0.01％–1％的范围内变化，以研究放电动力学和反应产物对水蒸气浓度（WVC）的依赖性。数值结果表明，放电的大多数特性敏感地取决于WVC。WVC的增加导致电子密度和放电传播速度的增加，这归因于He *和H 2 O之间的Penning电离。主阳离子从He +切换为H 2 O +，而WVC从0.01％至1％。主要的活性氧是OH，其峰值密度比O高约两个数量级。OH和O自由基的密度随WVC的增加而增加。结果表明，O自由基的形成机理具有重要意义。