Qualitative investigating on the effect of fine water spray and its orientation in mitigating vapour cloud explosions

Johnson, AS; Nasr, GG; Nourian, A; Abba, MK

Abstract

For past decades, various industries, such as oil and gas, have come to realisation that using water-based spraying systems, with fine very fine droplets should be the preferred option in mitigating and suppressing the thermal explosions. Previous studies have mainly focused on improving efficiency of flame mitigation by utilising existing water spray systems with droplets greater than 200 microns. This paper provide analysis in the utilisation of fine water sprays (between 10 to 30 microns) using Spill Return Atomisers (SRAs) to mitigate slow moving flames within the range of 5 to 30 m/s. The flame produced by a mixture of methane and air at four different Equivalent Ratios (ER, φ) between 0.61 to 1.06. Three different SRAs (Type A, B, and C) with variation in exit orifice are, also, placed in two different orientations (counter and parallel flow). The results indicate that by using single spray in both directions, atomisers Type-A and B are not capable of mitigating the flame at different equivalent ratio of methane/air mixture. However, atomiser Type-C shows full mitigation φ0.61. Therefore, to mitigate the flame with φ > 0.61, the density and volume flux of the water droplets within the flame path should be increased.

Citation

Johnson, A., Nasr, G., Nourian, A., & Abba, M. (2021, August). Qualitative investigating on the effect of fine water spray and its orientation in mitigating vapour cloud explosions. Presented at ICLASS 2021, 15th Triennial International Conference on Liquid Atomization and Spray Systems, Edinburgh, UK

• Presentation Conference Type: Other
• Conference Name: ICLASS 2021, 15th Triennial International Conference on Liquid Atomization and Spray Systems
• Conference Location: Edinburgh, UK
• Start Date: Aug 29, 2021
• End Date: Sep 2, 2021
• Publication Date: Aug 30, 2021
• Deposit Date: Sep 6, 2021
• Publicly Available Date: Sep 6, 2021
• Journal: ICLASS Edinburgh 2021
• Volume: 1
• Issue: 1
• Pages: 254
• DOI: https://doi.org/10.2218/iclass.2021.5989
• Publisher URL: https://doi.org/10.2218/iclass.2021.5989
• Related Public URLs: http://journals.ed.ac.uk/ICLASS_Edinburgh/index
• Additional Information: Event Type : Conference