Acetone PLIF visualization of the fuel distribution at plasma-enhanced supersonic combustion

•100 Hz Acetone PLIF is applied to characterize unburned fuel distributions in a plasma stabilized planewall supersonic combustor.•A plasma filament coupled to a transverse fuel jet in a supersonic flow is shown to enhance jet penetration, cross flow expansion, and initiate fuel jet breakup.•A significant unburned fuel distribution in a plasma generated separation region is identified.•The minimum plasma pulse duration for flowfield transition from initial conditions to a combustion pattern was determined.