A down-fired flame burner including a flame charger and one or more field electrodes configured to control flame shape and/or heat transfer to a chemical reactor is presented. Also described is a method for providing process heat includes projecting a down-fired flame in a heating volume, electrically charging the flame to carry a majority charge, and applying an electric field proximate the down-fired flame to control flame shape, heat transfer from the flame, or flame shape and heat transfer from the flame, and applying heat from the flame to a chemical reactor.