Reaction front propagation in a turbulent flow.

The propagation of reaction fronts in a turbulent fluid flow is studied by direct numerical simulations in two space dimensions. The velocity field is obtained from integrating the Navier-Stokes equation in two dimensions. We investigate the structure of the reaction front and the enhancement of the front propagation speed due to turbulent mixing. Consistently with earlier theoretical, predictions and experiments we find two qualitatively different regimes as the Damköhler number-the ratio of eddy turnover times and of the characteristic chemical time scale-is varied, corresponding to a distributed reaction zone and thin wrinkled fronts.