Open Access

ARTICLE

Large Eddy Simulation of Gasoline-Air Mixture Explosion in Long Duct with Branch Structure

by Chong Liu, Yang Du, Jianjun Liang, Hong Meng, Jian Wang, Peili Zhang

Army Logistics University, Chongqing, 401311, China

* Corresponding Author: Peili Zhang. Email:

(This article belongs to the Special Issue: EFD and Heat Transfer II)

Fluid Dynamics & Materials Processing 2020, 16(3), 537-547. https://doi.org/10.32604/fdmp.2020.09119

Received 13 November 2019; Accepted 11 December 2019; Issue published 25 May 2020

Abstract

Gas explosion is a process involving complex hydrodynamics and chemical reactions. In order to investigate the interaction between the flame behavior and the dynamic overpressure resulting from the explosion of a premixed gasoline-air mixture in a confined space, a large eddy simulation (LES) strategy coupled with sub-grid combustion model has been implemented. The considered confined space consists of a long duct and four branches symmetrically distributed on both sides of the long duct. Comparisons between the simulated and experimental results have been considered with regard to the flame structure, flame speed and overpressure characteristics. It is shown that the explosion process can qualitatively be reproduced by the numerical simulation. Due to the branch structure, vortices are generated near the joint of the branch and long duct. Vortices rotate in opposite directions in the different branches. When the flame propagates into the branch, the flame front is influenced by the flow field structure and becomes more and more distorted. The overpressure displays a similar behavior in the two branches which have a different distance from the ignition point. It is finally shown that the overpressure change law can directly be put in relation with the shape of flame front.

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