THERMAL SCIENCE

International Scientific Journal

Xinjie Huang

,

Junjie Hu

,

Hailong Ding

,

Xinyi Zhang

,

Xinyi Li

,

Changlong Wang

,

Pengyuan Zhang

STUDY ON COMBUSTION AND FLAME MERGING CHARACTERISTICS OF TWO N-HEPTANE LINE FIRES UNDER WIND SPEED, SPACING, AND GROOVE WIDTH

ABSTRACT
This paper studied the effects of wind speed, spacing and groove width on the combustion and flame merging characteristics of two n-heptane line fires. The experimental results show that the range of intermittent merging stage will increase with groove width; the greater the wind speed, the greater the probability of merging. At the non-merging stage, the influence of wind speed on the flame merging probability can be ignored. Under the influence of wind speed, mass loss rate per unit area, ṁ″, of the downstream pool fire is greater than that of the upstream pool fire, at the stages of fully merging and intermittent merging. While when the flame spacing increases to the non-merging stage, ṁ″ of the upstream pool fire begins to be gradually greater than that of the downstream pool fire. On the other hand, the downstream flame ṁ″ increases firstly and then decreases, while the upstream flame ṁ″ shows an increasing trend, with spacing distance. The smaller the groove width, the greater the value of ṁ". When the spacing is 0, ṁ″ is the smallest. It is found that with the increase of spacing, the flame length under all tested conditions increases firstly and then decreases, and the flame inclination angle decreases firstly and then increases.
KEYWORDS
line fire, flame merging probability, wind speed, flame spacing, mass loss rate per unit area
PAPER SUBMITTED: 2023-09-08
PAPER REVISED: 2024-01-25
PAPER ACCEPTED: 2024-01-30
PUBLISHED ONLINE: 2024-04-13
DOI REFERENCE: https://doi.org/10.2298/TSCI230908074H
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2024, VOLUME 28, ISSUE Issue 4, PAGES [3001 - 3012]
REFERENCES
  1. Ju, X., et al., Flame Attachment and Downstream Heating Effect of Inclined Line Fires, Combustion and Flame, 240 (2022), 112004
  2. Ji, J., et al., Prediction of Thermal Radiation Received by Vertical Targets Based on 2-D Flame Shape from Rectangular n-heptane Pool Fires with Different Aspect Ratios, Energy, 185 (2019), Oct., pp. 644-652
  3. Wan, H., et al., Experimental Study on Flame Radiant Heat Flux From Two Heptane Storage Pools and Its Application Estimating Safety Distance, Energy, 182 (2019), Sept., pp. 11-20
  4. Li, M., et al., Experimental Study and New-proposed Mathematical Correlation of Flame Height of Rectangular Pool Fire with Aspect Ratio and Mass Burning Rate, Energy, 255 (2022), 124604
  5. Zhang, X., et al., Flame Radiation Emission From Pool Fires under the Influence of Cross Air-Flow and Ambient Pressure, Combustion and Flame, 202 (2019), Apr., pp. 243-251
  6. Zhou, K., et al., Experimental Study on Flame Interaction and Geometrical Features of Two Identical Fires on A Slope, Fire Safety Journal, 126 (2021), 103463
  7. Tang, W., et al., Local Flame Attachment and Heat Fluxes in Wind-driven Line Fires, Proceedings of the Combustion Institute, 36 (2017), 2, pp. 3253-3261
  8. Wan, H., et al., Experimental Study on Horizontal Gas Temperature Distribution of Two Propane Diffusion Flames Impinging on an Unconfined Ceiling, International Journal of Thermal Sciences, 136 (2019), Feb., pp. 1-8
  9. Huang, Y., et al., Research on the Interaction Between Two Line Jet Fires with Unequal Heat Release Rate at Different Burner Distances, Fuel, 258 (2019), 116016
  10. Liu, Q., et al., Study on Coupled Combustion Behavior of Two Parallel Line Fires, Fire, 5 (2022), 1, pp. 1-15
  11. Wan, H., et al., Effects of Pool Size and Spacing on Burning Rate and Flame Height of Two Square Heptane Pool Fires, Journal of Hazardous Materials, 369 (2019), 5, pp. 116-124
  12. Liu, C., et al., Effects of Ullage Height on Heat Feedback and Combustion Emission Mechanisms of Heptane Pool Fires, Fire Safety Journal, 124 (2021), 103401
  13. Ji, J., et al., Physical Models of Flame Height and Air Entrainment of Two Adjacent Buoyant Turbulent Jet Non-premixed Flames with Different Heat Release Rates, Proceedings of the Combustion Institute, 38 (2021), 3, pp. 4907-4916
  14. Li, B., et al., Experimental Study on the Characteristics of Flame Merging and Tilt Angle from Twin Propane Burners under Cross Wind, Energy, 174 (2019), May, pp. 1200-1209
  15. Chen, Y., et al., Flame Interaction and Tilting Behavior of Two Tandem Adjacent Hydrocarbon Turbulent Diffusion Flames in Crosswind: An Experimental Quantification and Characterization, Fuel, 290 (2021), 119930
  16. Chen, Y., et al., Effects of Cross Air-flow and Burner Distance on Temperature Profile and Flame Morphology of Dual Tandem Pool Fires, Fuel, 317 (2022), 123220
  17. Tang, F., et al., Effects of Crosswind and Burner Aspect Ratio on Flame Characteristics and Flame Base Drag Length of Diffusion Flames, Combustion and Flame, 200 (2019), Feb., pp. 265-275
  18. Tang, F., et al., Mass Burning Rate and Merging Behaviour of Double Liquid Pool Fires Under Cross Winds, Proceedings of the Combustion Institute, 39 (2022), 3, pp. 4041-4052
  19. Yao, Y., et al., Scale Effect of Mass Loss Rates for Pool Fires in an Open Environment and in Tunnels with Wind, Fire Safety Journal, 105 (2019), Apr., pp. 41-50
  20. Shi, C., et al., Experimental Study on the Flame Height Evolution of Two Adjacent Hydrocarbon Pool Fires under Transverse Air-flow, Energy, 262 (2023), 125520
  21. Huang, X., et al., Effects of Spacing Distance and Heat Release Rate on Flame Merging and Burning Characteristics of Two Ultra-long Thin Line Fires, Journal of Thermal Analysis and Calorimetry, 147 (2022), 23, pp. 13961-13975
  22. Huang, X., et al., Effects of Groove Width, Spacing Distance and Ullage Height on Combustion and Flame Merging Characteristics of Two-Line N-heptane Pool Fires, Thermal Science and Engineering Progress, 42 (2023), 101900
  23. Huang, X., et al., Effects of Spacing Distance and Fuel Mass Thickness on Combustion and Flame Merging Characteristics of Two-Line Pool Fires, Case Studies in Thermal Engineering, 38 (2022), 102325
  24. Moffat, R., Describing the Uncertainties in Experimental Results, Experiment Thermal and Fluid Science, 1 (1988), 1, pp. 3-17
  25. Otsu, N., et al., A Threshold Selection Method from Gray-Level Histograms, IEEE Transactions on System, 9 (1979), 1, pp. 62-66
  26. Liu, N., et al., Interaction of Two Parallel Rectangular Fires, Proceedings of the Combustion Institute, 37 (2019), 3, pp. 3833-3841
  27. Thomas, H., et al., Merging of Horizontally and Vertically Separated Small-Scale Buoyant Flames, Fire, 4 (2021), 103390
  28. Meng, N., Experimental Study on Flame Merging Behaviors and Smoke Backlayering Length of Two Fires in a Longitudinally Ventilated Tunnel, Tunnelling and Underground Space Technology, 137 (2023), 105147
  29. Zhang, Z., et al., Experimental Study on Flame Height of Two Oil Tank Fires under Different Lip Heights and Distances, Process Safety and Environmental Protection, 139 (2020), July, pp. 182-190
PDF VERSION [DOWNLOAD]
Study on combustion and flame merging characteristics of two n-heptane line fires under wind speed, spacing, and groove width

© 2024 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, National Institute of the Republic of Serbia, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence