A new DBD microplasma burner for measuring the effect of nanosecond plasma discharge on burning velocity of methane-air flames

This paper presents the initial characterization of a new burner design to study the effect of non-thermal plasma discharge on combustion characteristics at atmospheric pressure. The burner allows stabilizing an inverted cone flame in a mixture owing through a perforated plate designed as a microplasma reactor. The design principle of the microplasma reactor is based on the dielectric barrier discharge scheme which helps to generate a stable non-thermal plasma discharge driven by nanosecond high voltage pulses in the burner holes. The consumed power and pulse energy have been calculated form simultaneously measurements of current and voltage of the electrical pulses. Time resolved measurements of direct emission spectra for nitrogen second positive system N2(C - B) have been done to determine the rotational and vibrational temperature of the plasma discharge. By fitting the spectra with SPECAIR simulation data, it was found that the rotational and vibrational temperatures are 550 K and 3460 K, respectively, for the discharge in air at atmospheric pressure. The influence of a high voltage (4 kV) pulsed nanosecond discharge on the laminar burning velocity of methane-air flame has been investigated over a range of equivalence ratios (0.55 - 0.75). The laminar burning velocity was calculated by conical flame area method which has been validated by other published data. The results show an increase of the burning velocity of about 100% in very lean (Phi= 0:55) flames as a result of the plasma discharge effect.