Influence of the interelectrode gap on the main characteristics of a pulsating transverse-longitudinal discharge in high-velocity multicomponent gas flows

A nonstationary, transverse-longitudinal electrode discharge is obtained and is generated in a wide variation range of external conditions: the air-flow velocity was varied from $150$ to $550$ m/s, the minimal interelectrode gap was varied from $0.2$ to $0.8$ mm, and the maximal pulsating discharge current was varied from $5.5$ to $16$ A. It is shown that an increase in the discharge current leads to an increase in the maximally attainable plasma channel length and a decrease in the longitudinal electric field and plasma loop pulsation frequency. An increase in the interelectrode gap leads to an increase in voltage across the discharge, the plasmachannel length, and the longitudinal electric field intensity in plasma, whereas the pulsation frequency of voltage across the discharge gap, discharge current, and plasma loop decreases. An increase in flow velocity leads to an increase in electric-field intensity in the plasma and discharge pulsation frequency, whereas the voltage drop across the discharge does not depend on the flow velocity, and the full plasma loop length decreases. It is shown that the addition of propane into the air flow entails an essential change in the dependence of the plasma-loop pulsation frequency on the flow velocity, discharge current, and propane equivalence ratio in the fuel mixture.