Abstract
This work is aimed examine the effect of ullage height (tank roof to fuel surface) on the flame behavior of turbulent diffusion flames. A series of experiments with eight ullage heights (h = 0–28 cm) were conducted. Propane was issued from a gas burner (D = 20 cm) with different fuel supply rates. Experimental results showed that the total flame consists of an upper flame (Lupper, outside the tray) and a down-reaching flame (L down , inside the tray). It was found that Ldown decreases with fuel supply flow rate and there is a critical fuel supply flow rate ( Q s,c), independent of the ullage height, above which there is no down-reaching flame. Depending on the ullage height and fuel supply rate, the flame behaviors can be divided into three regimes: (Ⅰ) restricted down-reaching, (Ⅱ) free down-reaching and (Ⅲ) no down-reaching. Based on the dimensionless analysis, correlations were developed to predict the down-reaching, upper, and total flame lengths, respectively. These correlations were validated against the experimental data in the paper and the previous literature. The present results are of importance to understand the flame behaviors for the burning of fires with large ullage heights and provide guidance in risk assessment of tank fires.
| Original language | English |
|---|---|
| Article number | 104054 |
| Journal | Fire Safety Journal |
| Volume | 142 |
| Early online date | 20 Nov 2023 |
| DOIs | |
| Publication status | Published (in print/issue) - 31 Jan 2024 |
Bibliographical note
Funding Information:This study was sponsored by the National Key R&D Program of China ( 2021YFB3201900 ), the Key Research and Development Program of National Fire and Rescue Administration ( 2022XFZD04 ) and the Fundamental Research Funds for the Central Universities ( 2023JCCXAQ05 ).
Publisher Copyright:
© 2023 Elsevier Ltd
Keywords
- Liquid fuel
- Turbulent diffusion flames
- Ullage height
- Down-reaching flame length
- Upper flame length
