Effect of pressure on the emission characteristics of surface dielectric barrier discharge plasma

•Emission characteristics of SDBD plasma are reported.•Inner gap width and pressure affects the SDBD plasma characteristics dramatically.•The result is very useful for the design of plasma aerodynamic actuator on the aircraft.

This paper reports an experimental study of the emission characteristics of the surface dielectric barrier discharge plasma under different pressure. N2(C3IIu) rotational temperature, electron temperature and density were used to quantify the plasma characteristics. At atmospheric pressure, when the inner gap width increases from 0 mm to 1 mm, emission characteristics change dramatically since the discharge is much more filamentary. N2(C3IIu) rotational temperature, electron temperature and density are much higher with inner gap width of 1 mm. Along with the pressure decreasing, discharge transitions from filamentary to glow mode around 45 Torr. Variation laws of N2(C3IIu) rotational temperature and electron density with inner gap width of 0 mm and 1 mm are different. While the variation law of electron temperature is similar. When the pressure is less than 8 Torr, plasma characteristics are very similar with inner gap width of 0 mm and 1 mm.