  In this article effect of radiation preheating of unburnt mixture by
propagating deflagration front is studied from the viewpoint of its ability to
form a promoting temperature gradient and trigger transition to detonation.
First, we investigate the effect of radiation preheating of the unburnt
mixtures, when they are traveling through the wrinkles on the flame surface, in
order to estimate a possibility of significant temperature rise. Subsequently,
numerical simulations of a simplified mathematical model are carried out. They
demonstrate plausibility of the proposed mechanism of the deflagration to
detonation transition.
