表达式:火独立的两光子吸收激光诱导的光原子在高热的空气-碳气体-表面相互作用中
Applied spectroscopy
|December 11, 2025
概括
一种新的激光诱导光技术在高度等离子体中测量原子,而无需火. 这种方法在各种等离子体条件下揭示了在削减石墨附近的原子分布,这对于超音速研究至关重要.
科学领域:
- 航空航天工程 航空航天工程
- 等离子体物理学的物理学
- 材料科学 材料科学 材料科学
背景情况:
- 原子对于理解高超音速空气/碳气表面相互作用至关重要.
- 在高能设施中精确测量原子是具有挑战性的,因为火效应.
研究的目的:
- 提出一种新的火独立技术,用于测量原子,使用二光子吸收激光诱导的光.
- 应用这种技术来研究在等离子体羽中,在废弃石墨表面附近的原子分布.
主要方法:
- 利用高激光强度来确保光电化主导激发状态的人口减少.
- 研究了三个等离子体条件:17 MJ/kg空气 (145 W/cm2),18 MJ/kg空气 (195 W/cm2) 和24 MJ/kg (85 W/cm2).
- 在停滞流线沿着空间解析的原子数密度.
主要成果:
- 在纯等离子体中观察到最高的原子密度.
- 195W/cm2的空气等离子条件显示了第二高的原子分布.
- 在145W/cm2的空气等离子条件下,在测试条件中,原子分布是最低的.
结论:
- 这种以光离子化为主导的技术有效地测量了高能环境中的原子.
- 这种方法在超音速条件下为空气/碳相互作用提供了有价值的数据.
- 该研究强调了等离子体组成和能量流在原子分布上的重要性.
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