Turbulent boundary layer control with a spanwise array of DBD plasma actuators

The turbulent boundary layer control on NACA 0012 airfoil with Mach number ranging from 0.3 to 0.5 by a spanwise array of dielectric barrier discharge (DBD) plasma actuators by hot-film sensor technology is investigated. Due to temperature change mainly caused through heat produced along with plasma will lead to measurement error of shear stress measured by hot-film sensor, the correction method that takes account of the change measured by another sensor is used and works well. In order to achieve the value of shear stress change, we combine computational fluid dynamics computation with experiment to calibrate the hot-film sensor. To test the stability of the hot-film sensor, seven repeated measurements of shear stress at Ma = 0.3 are conducted and show that confidence interval of hot-film sensor measurement is from −0.18 to 0.18 Pa and the root mean square is 0.11 Pa giving a relative error 0.5% over all Mach numbers in this experiment. The research on the turbulent boundary layer control with DBD plasma actuators demonstrates that the control makes shear stress increase by about 6% over the three Mach numbers, which is thought to be reliable through comparing it with the relative error 0.5%, and the value is hardly affected by burst frequency and excitation voltage.