Results 111 to 120 of about 5,124 (165)

Flame acceleration and transition to detonation in ducts

Progress in Energy and Combustion Science, 2008
This paper reviews the state of knowledge on flame acceleration and deflagration-to-detonation transition (DDT) in smooth ducts and ducts equipped with turbulence-producing obstacles. The objective is to bring to light the basic understanding of the phenomenon and its application to explosion safety. The scope of the review is restricted to homogeneous
Gabriel Ciccarelli, S Dorofeev
exaly   +2 more sources

The role of shock–flame interactions on flame acceleration in an obstacle laden channel

Combustion and Flame, 2010
Abstract Flame acceleration was investigated in an obstructed, square-cross-section channel. Flame acceleration was promoted by an array of top and bottom surface mounted obstacles that were distributed along the entire channel length at an equal spacing corresponding to one channel height.
Gabriel Ciccarelli, Craig Johansen
exaly   +2 more sources

Flame–turbulence interactions during flame acceleration using solid and fluid obstacles [PDF]

Physics of Fluids, 2022
A combination of solid and transverse jet obstacles is proposed to trigger flame acceleration and deflagration-to-detonation transition (DDT). A numerical study of this approach is performed by solving the reactive Navier–Stokes equations deploying an adaptive mesh refinement technique.
Wandong Zhao, Jianhan Liang, Ralf Deiterding, Xiaodong Cai, Xinxin Wang   +4 more
openaire   +2 more sources

Explosion triggering by an accelerating flame

Physical Review E, 2006
The analytical theory of explosion triggering by an accelerating flame is developed. The theory describes the structure of a one-dimensional isentropic compression wave pushed by the flame front. The condition of explosion in the gas mixture ahead of the flame front is derived; the instant of the explosion is determined provided that a mechanism of ...
Bychkov, Vitaly, Akkerman, V'yacheslav
openaire   +3 more sources

Statistical Study of Accelerating Flames

The Physics of Fluids, 1960
Study of velocity fluctuations observed by means of ionization probes during the development of detonation reveals its significance as an indicator of physical characteristics of the flame. The scatter in time of arrival (the reciprocal of the velocity) was found normally distributed at an 85% probability level.
Stern, Raul A., Ladermann, A. J., Oppenheim, Antoni K.   +2 more
openaire   +1 more source

Investigation of Flame Regimes for Flame Acceleration to Detonation

2018 Joint Propulsion Conference, 2018
Expanding hydrogen-air flames are studied in a semi-confined duct with an optical access test section. The focus of the work is to characterize the regimes of flame development in a highly turbulent environment and observe the Deflagration-to-Detonation (DDT) phenomenon.
Chambers, Jessica M., Ahmed, Kareem A.
openaire   +2 more sources

Theory and modeling of accelerating flames in tubes

Physical Review E, 2005
The analytical theory of premixed laminar flames accelerating in tubes is developed, which is an important part of the fundamental problem of flame transition to detonation. According to the theory, flames with realistically large density drop at the front accelerate exponentially from a closed end of a tube with nonslip at the walls.
Vitaly, Bychkov, Arkady, Petchenko, V'yacheslav, Akkerman, Lars-Erik, Eriksson   +3 more
openaire   +2 more sources

Acceleration Effects on the Stability of Flame Propagation

SIAM Journal on Applied Mathematics, 1979
We consider the effect of acceleration on the diffusional thermal instability of a plane flame front in a premixed gaseous mixture. We recall that the diffusional thermal instability occurs if the Lewis number L of the mixture is less than a critical value $L_0 $.
Matkowsky, B. J., Sivashinsky, G. I.
openaire   +2 more sources

Convergence Acceleration for Steady Flame Computations

Journal of Computational Physics, 2000
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Cuenot, B., Angelberger, C., Legier, J.-P.   +2 more
openaire   +1 more source

Physical Mechanism of Ultrafast Flame Acceleration

Physical Review Letters, 2008
We explain the physical mechanism of ultrafast flame acceleration in obstructed channels used in modern experiments on detonation triggering. It is demonstrated that delayed burning between the obstacles creates a powerful jetflow, driving the acceleration. This mechanism is much stronger than the classical Shelkin scenario of flame acceleration due to
Vitaly, Bychkov, Damir, Valiev, Lars-Erik, Eriksson   +2 more
openaire   +2 more sources