Details
Title | Effect of Obstacle Shape on Flame Acceleration and Transition to Detonation in an Obstructed Channel // Proceedings of the Ninth International Seminar on Fire and Explosion Hazards: 21-26 April 2019, Saint Petersburg, Russia. Vol. 1 |
---|---|
Creators | Xiao H. ; Oran E. S. |
Organization | University of Science and Technology of China ; University of Maryland |
Imprint | Saint Petersburg, 2019 |
Collection | Общая коллекция |
Document type | Article, report |
File type | |
Language | English |
DOI | 10.18720/SPBPU/2/k19-111 |
Rights | Свободный доступ из сети Интернет (чтение, печать, копирование) |
Record key | RU\SPSTU\edoc\61205 |
Record create date | 6/18/2019 |
Numerical simulations were conducted to understand the effect of obstacle shape on flame acceleration and deflagration-to-detonation transition (DDT) through an array of obstacles in a channel. The multidimensional, fully compressible reactive Navier-Stokes equations, coupled to a calibrated chemicaldiffusive model for combustion of a stoichiometric hydrogen-air mixture, were solved using a high-order algorithm with adaptive mesh refinement (AMR). While maintaining the same blockage ratio, the influence of obstacle shape on DDT was examined with circular, square, and triangular obstacles. The simulations show that the shape of the obstacle plays an important role in flame acceleration and detonation initiation. Squares create spaces between obstacles and walls, and these spaces provide a path that leads to the fastest flame acceleration and shortest detonation initiation time compared to circular and triangle obstacles. The presence of sharp angles on the triangular obstacles is favorable for flame stretching and convolution, and this facilitates flame acceleration and transition to detonation. The round, circular obstacles have the least effect on promoting flame acceleration and DDT. Although there are differences in flame acceleration and DDT among differently shaped obstacles, the basic mechanism for detonation initiation is similar in all of the cases studied and involves shock interactions with flame front.
Access count: 986
Last 30 days: 38