Influence of electrical discharges on combustion (generalized Borghi diagram)

There are several mechanisms associated with the thermal, kinetic, and electromechanical influence of electrical fields on burning of mixes. Here, it is shown that the burning processes in the presence of the electrical fields involve, along with the known criteria, an additional criterion that is describing the processes arisen from affecting of the electrical discharges on mix, ignition and flame propagation. The role of D or A electrical fields and/or their influence on the induction time of combustion, temperature of ignition, the borders of a steady burning area, the laminar and turbulent flames propagation, and the flame flat front stability are shortly examined. Specially, affecting the combustion by an external electric field through the overheating turbulence and streamer branching is discussed. Problems of low-temperature plasma instabilities and plasma turbulence are shortly studied. The effects of the overheating instability development and generating a specific kind of turbulence during the electrical discharge burning are discussed. The modified Karlovitz $\Lambda_{\rm K}$, Damköler $\Lambda_{\rm D}$ criteria and the generalized Borghi diagram that divides the space of non-dimensional parameters into branches of different flame behavior are presented.