Propagation of turbulent burning of methane-air mixtures in tubes

A simplified mathematical model for turbulent flows, which may be called a “two-phase” approximation with respect to one of possible methods of deriving corresponding equations for time-averaged quantities, is proposed. In a one-dimensional approximation, the problem of propagation of a turbulent flame that arises near the butt end of a semi-infinite smooth tube is solved. On the basis of the infinitely thin flame front model, the range of concentrations in which turbulent burning modes with a constant flame-propagation velocity exist is determined.