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Comparison of two flow measurement devices for use in fire experiments
Giovanni Di Cristina1, Rodney A Bryant1
1National Institute of Standards and Technology, Fire Research Division, Engineering Laboratory, Gaithersburg, MD, USA.
Proceedings of the Combustion Institute. International Symposium on Combustion
|October 25, 2024
Summary
S-type pitot probes (S-probes) offer an accurate and reliable alternative to bi-directional probes for measuring fire-induced flows. These probes demonstrate comparable or superior performance, especially in turbulent conditions.
Area of Science:
- Fire Science
- Fluid Dynamics
- Instrumentation
Background:
- Bi-directional probes are essential for measuring dynamic fire-induced flows but are not commercially available, requiring custom fabrication.
- S-type pitot probes (S-probes) operate on similar principles to bi-directional probes and offer advantages in manufacturing and calibration.
Purpose of the Study:
- To characterize and compare the performance of S-probes against bi-directional probes and pitot-static probes.
- To evaluate probe accuracy in both steady, well-characterized flow and turbulent jet flow conditions.
Main Methods:
- Experimental comparison of S-probes and bi-directional probes against pitot-static probes.
- Measurements conducted in a controlled wind tunnel with steady flow.
- Velocity profile measurements in a turbulent jet generated by a blower fan.
Main Results:
- S-probes exhibit accuracy comparable to or exceeding that of bi-directional probes across tested scenarios.
- In turbulent jet flow, S-probe measurements in the core region were within 2% of pitot-static probe measurements.
- Bi-directional probes showed a larger deviation (within 6%) from pitot-static measurements in the turbulent jet core.
Conclusions:
- S-probes are a viable and accurate alternative to bi-directional probes for fire flow measurements.
- S-probes maintain high accuracy in both conditioned and turbulent flow environments.
- The reliable manufacturing and calibration of S-probes make them a practical choice for researchers.
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