Heating of the fuel mixture due to viscous stress ahead of accelerating flames in deflagration-to-detonation transition
Artikel i vetenskaplig tidskrift, 2008

The role of viscous stress in heating of the fuel mixture in deflagration-to-detonation transition in tubes is studied both analytically and numerically. The analytical theory is developed in the limit of low Mach number; it determines temperature distribution ahead of an accelerating flame with maximum achieved at the walls. The heating effects of viscous stress and the compression wave become comparable at sufficiently high values of the Mach number. In the case of relatively large Mach number, viscous heating is investigated by direct numerical simulations. The simulations were performed on the basis of compressible Navier-Stokes gas-dynamic equations taking into account chemical kinetics. In agreement with the theory, viscous stress makes heating and explosion of the fuel mixture preferential at the walls. The explosion develops in an essentially multi-dimensional way, with fast spontaneous reaction spreading along the walls and pushing inclined shocks. Eventually, the combination of explosive reaction and shocks evolves into detonation.

NONSLIP

WIDE TUBES

WALLS

CURVED STATIONARY FLAMES

SIMULATION

PROPAGATION

MECHANISM

Författare

D. M. Valiev

Kungliga Tekniska Högskolan (KTH)

Umeå universitet

V. Bychkov

Umeå universitet

V. Akkerman

Umeå universitet

Lars-Erik Eriksson

Chalmers, Tillämpad mekanik, Strömningslära

M. Marklund

Umeå universitet

Physics Letters, Section A: General, Atomic and Solid State Physics

0375-9601 (ISSN)

Vol. 372 4850-4857

Ämneskategorier

Maskinteknik

DOI

10.1016/j.physleta.2008.04.066