Geometrical and electrical optimization of NS-SDBD streamwise plasma heat knife for aircraft anti-icing

Ice accretion on aircraft encountering supercooled water droplets in clouds poses great risks to flight performance and safety.With the aim of optimizing the newly developed streamwise plasma heat knife method for anti-icing,a parametric investigation is carried out in this work.The influence of the detailed voltage profile on the heating effects of a Surface Dielectric Barrier Discharge driven by Nanosecond Pulses(NS-SDBD)is investigated,and a comparison of the antiicing performance among different configurations of streamwise plasma heat knife is made.The results show that columnar high-temperature regions produced by a multi-streamer discharge appear at small pulse rise time,but become diffuse as the pulse rise time increases.An optimal pulse rise time exists to provide a wide range and high value of temperature,which is found to be 150 ns for the setup in the present study.The influence of the pulse fall time is much weaker than that of the rise time.The range and value of the temperature decrease with increasing pulse fall time.A greater pulse width is found to improve the heating effect by increasing the discharge power.When a spanwise electrode is placed connecting the streamwise electrodes of the streamwise plasma heat knife at the airfoil leading edge,the anti-icing performance becomes poorer,whereas good performance is achieved when the spanwise electrode is at the edge of the streamwise electrodes.Based on this,a three-level configuration of the plasma heat knife is proposed,and its anti-icing performance is found to be much better than that of the original configuration.