Investigation of the effects of N₂ and CO₂ on the overpressure hazards, flame behaviors and reaction kinetics of LPG/air explosions

ABSTRACT

To research the influence of inert gases on the explosion behaviors of LPG/air mixtures, LPG explosion tests suppressed by CO₂ and N₂ were conducted in a spherical chamber and the chemical reaction kinetic properties were analyzed. The results show that CO₂ has a better inhibitory effect than N₂, especially when the added amount is small. With the increasing volume fraction of inert gases, the LPG explosion flame propagation speed continuously decreases, and the phenomenon of flame uplift and wrinkling deformation occurs. The explosion pressure of LPG/CO₂(N₂)/air mixture and the average flame propagation speed in the initial stage follow an exponential function with an offset. The laminar flame structure of 4% LPG is similar to its mixtures with N₂ and CO₂. After adding inert gases, the maximum temperature of the LPG laminar flame decreases significantly, and the flame thickness increases. The key elementary reactions affecting the N₂(CO₂)/LPG/air explosions are given. The research results have important implications for suppression of LPG explosions.

KEYWORDS:

• LPG
• inert gas
• explosion severity
• flame propagation
• reaction kinetics

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work is supported by the Research Start-up Fund of Changzhou University [Grant No. ZMF23020084], the National Natural Science Foundation of China [Grant No. 52304205; 52104230], and the Subtopics of National Key Research and Development Program [Grant No. 2022YFC3003302].

Notes on contributors

Song Lin

Song Lin earned his Doctoral Degree in Safety Science and Engineering of China University of Mining and Technology in 2022. At present, he is a Lecturer in Changzhou University. His research interests include gas/dust explosion prevention and reaction mechanism.

Zhentang Liu

Zhentang Liu is a Professor in China University of Mining and Technology. His research focuses on mine ventilation, explosion accident prevention.

Xiaomeng Chu

Xiaomeng Chu earned her Master Degree in Safety Engineering of China University of Mining and Technology in 2023. Her research focuses on gas explosion and prevention.

Yan Tang

Yan Tang earned his Doctoral Degree in Safety Science and Engineering of China University of Mining and Technology in 2019. At present, he is a Lecturer in Changzhou University. His research focuses on fire and chemical safety.

Dong Chen

Dong Chen is an Associate Professor in China University of Mining and Technology. His research interests include impact dynamics, microseismic monitoring and early warning.