# Icing Mitigation by MEMS-Fabricated Surface Dielectric Barrier Discharge
## 6 Summary  
MEMS-fabricated SDBDs were investigated for their anti- and de-icing capability. The samples based on the dielectrics borofloat glass and zirconia with PVD-evaporated \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Publication**} & \multirow{2}{*}{**Technology**} & **Discharge Power** & **System Power** & **Temperature** & **Wind Speed** & **LWC** \\  & & [ kW/m\({}^{2}\)] & [ kW/m\({}^{2}\)] & [°C] & [m/s] & [g/m\({}^{3}\)] \\ \hline [PERSON] et al. [54] & heating device & \(-\) & 92 & \(-5\) & 90 & 2 \\ [PERSON] et al. [55] & heating device & \(-\) & 62 & \(-5\) \& \(-20\) & 21 & 0.4 \\ [PERSON] et al. [22] & pulsed-SDBD, grid & 8.3 & 31 & \(-7\) & 90 & 0.5 \\ [PERSON] et al. [22] & pulsed-SDBD, stripes & 7.3 & 28 & \(-7\) & 90 & 0.5 \\ current work & glass/PCB SDBD & 3.1 \(\pm\) 0.3 & \(19\pm 1\) & \(-17.5\pm 1\) & 27 \& 50 & 3 \\ current work & zirconia SDBD & 8.9 \(\pm\) 1 & \(27\pm 2\) & \(-20\) & 30 & 3 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Comparison of the power consumption for different anti-icing technologies. The discharge power is the power consumption obtained from the QV-plots which is only applicable for the SDBDs. The system power includes the power required to generate the high voltage. The last there columns present the parameters of the iCORE. The temperature of the supercooled droplets, ice wind speed and the liquid water content (LWC). Chrome-Nickel and Titanium electrodes were successfully tested in the icing wind tunnel at air speeds between 27 m s\({}^{-1}\) and 50 m s\({}^{-1}\), and a temperature of \(-18\,\mathrm{\SIUnitSymbolCelsius}\). The air speed was restricted due to an insufficient robustness of the borofloat SDBD against mechanical stress caused by the aerodynamic load. The performance of the MEMS-manufactured SDBDs has been compared to conventional SDBDs that were realized using printed circuit board (PCB) technology with FR-4 as substrate. The surface roughness of all tested substrates was below 1 m and had no discernible impact on the ice accretion. Similarly, the 200 nm thick MEMS-electrodes did not act as icing initiators, contrary to the 35 m PCB-electrodes. Note that the minimum thickness of PCB electrodes is limited to about 17 m for technical feasibility reasons. This unambiguously indicates an advantage of the MEMS-samples for anti-icing applications due to the unique ability to manufacture sub-micrometer thick electrodes. It is important to note that the surface wettability plays a crucial role for conceivable anti-icing applications. Hydrophobic substrates demonstrate a better performance when the SDBD is inactive and should therefore be preferred. [PERSON] et al. [58] showed that the wettability of zirconia can be influenced with the manufacturing process, which could improve further iterations of zirconia SDBDs. We showed that the anti-icing effect is independent on the ionic wind, which would require a certain minimum thickness of the substrate to avoid the actuator saturation mode. Therefore, the use of thin-film substrates can reduce the ignition voltage. Worst case estimations clearly prove that the electrical power dissipated in the dielectric does not exceed 30% of the total SDBD-power. A large part of the power is converted by the plasma which extends only a few millimeters above the surface. This fact underscores the potential of low-temperature plasma anti-icing systems in which, unlike thermal systems, the energy is not first converted into heating of the bulk substrate, which then melts the ice in a subsequent process. We hypothesize that an optimized SDBD tuned to the local icing severity by varying the electrode density and the dielectric thickness will result in a drastic improvement in efficiency. The following are available at [[https://www.mdpi.com/article/10.3390/app112311106/sl](https://www.mdpi.com/article/10.3390/app112311106/sl)]([https://www.mdpi.com/article/10.3390/app112311106/sl](https://www.mdpi.com/article/10.3390/app112311106/sl)). See Supplementary-Lindner.pdf.