On a television show, a pre-cooled bare-skinned person (TV host) passed through engulfing kerosene flames. The assumption was that a water film should protect him during 0.74 s flame exposure in an environment of 86 kW/m 2 heat flux. The TV host got light burn inflammation on the back, arms and legs. The present work studies skin temperatures and burn damage integral of such dangerous flame exposure. The skin temperature distribution during water spray pre-cooling, transport to the flames, flame exposure, transport to the water pool, and final water pool cooling is modelled numerically. Details of the temperature development of the skin layers are presented, as well as the associated damage integral. It is shown that 5 °C water spray applied for a 30 s period pre-cooled the skin sufficiently to prevent severe skin injury. Soot marks indicate that the water layer evaporated completely in some areas resulting in skin flame contact. This exposed dry skin directly to the flames contributing significantly to the damage integral. It is further analyzed how higher water temperature, shorter pre-cooling period or longer flame exposure influence the damage integral. It is evident that minor changes in conditions could lead to severe burns and that high heat flux levels at the end of the exposure period are especially dangerous. This flame stunt should never be repeated.
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机译：在电视节目中，一个预先冷却的皮肤裸露的人（电视主持人）穿过了吞噬的煤油火焰。假设在热通量为86 kW / m 2的环境中，水膜应在0.74 s的火焰暴露期间为他提供保护。电视主持人的背部，手臂和腿部受到轻度烧伤炎症。目前的工作研究皮肤温度和这种危险火焰暴露的烧伤损害积分。对水喷雾预冷却，运输到火焰，暴露于火焰，运输到水池以及最终水池冷却期间的皮肤温度分布进行数值建模。介绍了表皮层温度变化的详细信息以及相关的损坏积分。结果表明，在30 s的时间内喷洒5°C的水可以充分冷却皮肤，以防止严重的皮肤伤害。烟灰痕迹表明水层在某些区域完全蒸发，导致皮肤火焰接触。这种干燥的皮肤直接暴露在火焰中，对损坏的整体影响很大。进一步分析了较高的水温，较短的预冷却时间或较长的火焰暴露如何影响损伤积分。显然，条件的微小变化可能导致严重的灼伤，并且暴露期结束时的高热通量水平尤其危险。绝不能重复这种火焰特技。
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