Abstract Smoke release in the limited volume of a spaceship poses a major threat to the life of astronauts in long range exploration missions. If the absence of buoyant flows fundamentally affects combustion mechanisms, the possibility of atmospheric design in spacecraft environment provides a new leverage, not usually available on Earth. Investigating a non-buoyant flame spreading over the polyethylene coating of an electrical wire in an opposed laminar flow, the previous paper highlighted how flow conditions, namely oxygen content, flow velocity, and ambient pressure, affected spread rate and soot formation rate. The implementation of the Broadband Modulated Absorption/Emission (B-MAE) technique provided mappings of soot temperature and volume fraction in the spreading flames during parabolic flights. In this second paper, the link between these microscopic observations and new macroscopic findings regarding the influence of flow conditions on the smoke production of a flame in the same configuration is presented. Taking into account other requirements of space exploration, atmospheric conditions below normoxic values present a clear interest from a fire safety perspective. In the process, a threshold temperature at which soot oxidation reactions are frozen is identified. The value of 1400 K brought forward conforms with past measurements performed at normal gravity, while discrepancies with previous microgravity measurements are addressed. Given the broad capability of human lungs to adapt to various conditions, the overall mapping of smoke production as a function of flow conditions is a valuable tool for atmospheric design considerations.

中文翻译：

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逆流条件对非浮力火焰在聚乙烯涂层线上蔓延的影响——第二部分：烟尘氧化淬火和烟雾释放

摘要 宇宙飞船有限体积内的烟雾释放对执行远程探索任务的宇航员的生命构成了重大威胁。如果没有浮力流从根本上影响燃烧机制，航天器环境中大气设计的可能性提供了一种新的杠杆，通常在地球上不可用。前一篇论文研究了在反向层流中非浮力火焰在电线的聚乙烯涂层上蔓延，强调了流动条件（即氧含量、流速和环境压力）如何影响蔓延速率和烟灰形成速率。宽带调制吸收/发射 (B-MAE) 技术的实施提供了抛物线飞行期间蔓延火焰中烟灰温度和体积分数的映射。在这第二篇论文中，介绍了这些微观观察与新的宏观发现之间的联系，这些发现涉及流动条件对相同配置中火焰烟雾产生的影响。考虑到太空探索的其他要求，从消防安全的角度来看，低于正常含氧量值的大气条件表现出明显的兴趣。在该过程中，确定了使碳烟氧化反应冻结的阈值温度。提出的 1400 K 值与过去在正常重力下进行的测量一致，同时解决了与以前微重力测量的差异。鉴于人肺适应各种条件的广泛能力，作为流动条件的函数的烟雾产生的整体映射是大气设计考虑的宝贵工具。