# Experimental Study on Anti-Icing Performance of NS-DBD Plasma Actuator
## 1 Introduction
[PERSON] et al. [19] and [PERSON] et al. [20] have proposed that the energy released at the edge of the exposed electrode accounts for the hemispheric part of the pressure waves, while the energy deposition during filament propagation produces the straight part. [PERSON] et al. [23] showed that the gas temperature in the discharge volume can be  
Figure 1: Sketch of a DBD plasma actuator. Figure 2: Characteristic schlieren images of the pressure wave induced by NS-DBD from two observation directions [20]. momentarily heated to 1000 K in the order of nanoseconds. [PERSON] et al. [24] indicated that local air is heated to as much as 1100 K after the pulse, before decreasing to 310 K at a rate of k = \(-\)225/t Ks\({}^{-1}\). It has also been pointed out that the heating area of the gas corresponds well with the extension of the plasma, spreading only a few mms. Quantitative experimental measurements of heated gas near the dielectric surface are quite difficult, due to the spatial and temporal scales involved. [PERSON] et al. [25] revealed that the N2(C3 Gu) rotational temperature of the NS-DBD actuator is about 400 K. As for the effect of electrical parameters on discharge characteristics, [PERSON] et al. [26] found that the NS-DBD filament length increases with the rise of applied voltage amplitude, and the filamentous discharge gets more intense with an increase of frequency. Thus, the pulse frequency and voltage amplitude of electric actuation signal has a great influence on the discharge characteristics. Attracted by the thermal effect and flow control effect of plasma actuation, [PERSON] et al. [27] proposed the use of an AC-DBD plasma actuator for icing control; an experiment under the conditions of wind speed (15 m/s) and temperature (\(-\)10 \({}^{\circ}\)C) was conducted to confirm the de-icing and anti-icing performances of plasma actuation. Subsequently, [PERSON] et al. [28] conducted an experiment to evaluate the anti-icing performance of AC-DBD and found it has better performance in comparison to that of a conventional electrical heating method. In view of the attractive thermal effect of NS-DBD plasma actuation, [PERSON] et al. [29] conducted a numerical analysis of the anti-icing performance of a NS-DBD plasma actuator; the results showed that the plasma anti-icing method could protect airfoil from icing. The de-icing capacity of the NS-DBD plasma actuator has also been experimentally verified on an iced plate [30]. However, the anti-icing performance of NS-DBD plasma actuation and the influence of pulse frequency and voltage amplitude of electric actuation signal have not yet been evaluated. Higher voltage can lead to larger discharge area, while higher pulse frequency brings about more times of discharge per unit of time. The increase of both voltage amplitude and pulse frequency can bring about an increase of energy consumption. Taking energy consumption into consideration, two typical discharge conditions were selected in this study. The first is HV-LF discharge, corresponding to discharge under higher voltage amplitude with lower pulse frequency; the second is LV-HF discharge, comprising discharge under a lower voltage amplitude but higher pulse frequency. With the same power consumption, experiments on the anti-icing performance of two different discharge conditions were conducted. The process of anti-icing and the surface temperature distribution of plasma actuator were analyzed through a CCD camera and infrared thermal imager, with the objective of exploring the anti-icing mechanism of NS-DBD plasma actuation.