两种用于火灾实验的流量测量装置的比较
Giovanni Di Cristina1, Rodney A Bryant1
1National Institute of Standards and Technology, Fire Research Division, Engineering Laboratory, Gaithersburg, MD, USA.
概括
S型皮托探头 (S探头) 为测量火灾引起的流量提供了对双向探头的准确和可靠的替代方案. 这些探测器表现出同等或更高的性能,特别是在动荡的条件下.
科学领域:
- 消防科学 消防科学 消防科学
- 流体动力学 流体动力学
- 仪器化 仪器化 仪器化
背景情况:
- 双向探头对于测量动态火灾引起的流量至关重要,但在商业上没有,需要定制制造.
- S型皮托探头 (S探头) 运行原理与双向探头相似,在制造和校准方面具有优势.
研究的目的:
- 描述和比较S探头与双向探头和皮托静态探头的性能.
- 为了评估探测器在稳定,有良好的特征的流量和流喷流条件下的准确性.
主要方法:
- 对比S探头和双向探头与皮托静态探头的实验比较.
- 在控制的风洞中进行的测量,流量稳定.
- 在一个由吹风扇产生的流喷气中测量速度概况.
主要成果:
- 在经过测试的场景中,S探头的精度与双向探头的精度相当或超过.
- 在流喷流中,核心区域的S探头测量在皮托静态探头测量的2%以内.
- 双向探测器显示了流喷气核心中比特静态测量的较大偏差 (在6%以内).
结论:
- S-探头是用于火流测量的双向探头的可行和准确的替代方案.
- 在条件和流环境中,S探头保持高精度.
- S探头的可靠制造和校准使其成为研究人员的实用选择.
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