A Study of the Mean and Turbulent Structure of a Free Jet and Jet Impingement Heat Transfer

Donaldson, Coleman duP.; Snedeker, Richard S.; Margolis, D. P.

doi:10.21236/ad0656592

Cited by 2 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The key parameter controlling the structure of the under-expanded jet flow field is the nozzle pressure ratio (NPR), defined as the ratio of the total incoming jet pressure 𝑝 0 to the ambient pressure𝑝 ∞ . Donaldson et al [87] pointed out that the jet pressure ratio satisfied 𝑝 0 /𝑝 ∞ > 3.83 that highly under-expanded jet took shape. The alteration of the flow field's structure occurs as a consequence of enhancing the pressure ratio of the entering flow.…”

Section: Description Of the Out-of-tube Jet Fire Phenomenon Under-exp...mentioning

confidence: 99%

Safe use of hydrogen energy: review on hydrogen self- ignition and generated hydrogen jet fire

Zhi,

Li,

Zhou

et al. 2024

Preprint

View full text Add to dashboard Cite

In the fight against climate change, hydrogen is seen as a promising sustainable energy alternative to fossil fuels. However, its wider adoption has raised safety issues, particularly regarding spontaneous combustion without an external spark. To ensure safe and sustainable hydrogen use, researchers have developed a thorough research approach targeting hydrogen's potential for spontaneous combustion. Progress has been made in understanding this phenomenon within transparent extension tubes, examining various factors like tube dimensions, curvature, shape, and rupture disc properties. These studies have revealed consistent trends. Simulations have helped explain how hydrogen auto-ignites, often starting at the tube wall, especially in high-pressure situations where it interacts with hot air and expands cold fuel. Researchers have also created mathematical models related to ignition dynamics. Yet, there's limited experimental data on hydrogen jet self-ignition in open spaces. Some simulations suggest that high-pressure hydrogen can ignite spontaneously even without a confinement, but the ignition event is so brief that it's difficult to capture experimentally. Moreover, scholars are creating more accurate empirical formulas based on extensive experimental statistics that connect internal tube ignition to external jet flames. The accuracy of these empirical estimates improves as more experimental data becomes available.

show abstract

Section: Description Of the Out-of-tube Jet Fire Phenomenon Under-exp...mentioning

confidence: 99%