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This paper focuses on the shock wave/boundary layer interaction (SWBLI) at the compression corner. The concept of dynamic microvortex generator (Dy-MVG) is proposed based on the flow control mechanism. A high-precision drive system is used to control the periodic oscillation of the microvortex generator, thereby injecting controllable dynamic disturbances into the boundary layer. Based on the Feng Dong (FD)-06 wind tunnel, the control effect and mechanism of Dy-MVG on SWBLI are investigated by schlieren and pulsating pressure test techniques. The operating conditions are as follows: the incoming Mach number is 2.5 and 3.5, the total temperature is 300 K, and the oscillation frequency of the Dy-MVG is 2–60 Hz. The results show that classical MVG moves the shock foot position downstream and increases the shock angle. Dy-MVG enables dynamic changes in the shock foot position and shock angle over a greater range than classical MVG. Compared with classical MVG, Dy-MVG further weakens the shock intensity in the SWBLI region, and the shock intensity decreases with the increase of excitation frequency. Dy-MVG further increases the pulsating pressure and the energy of low-frequency characteristics in the SWBLI region, resulting in better control of the SWBLI. The Dy-MVG proposed in this paper has better performance than the classical MVG in controlling SWBLI. Due to the adjustable characteristics of Dy-MVG, it can be applied to a wide speed range of aircraft. For example, it can be used for airfoil flow control to improve airfoil characteristics, and it can also be applied to the inlet to improve the inlet performance. The frequency and amplitude can be controlled to meet the requirements of airfoil and inlet under different flight conditions. [ABSTRACT FROM AUTHOR]

In order to meet the demanding drag reduction requirements of high-speed aircraft, the drag reduction mechanism of array microslit-opposed jets in the passivation leading edge is studied using a numerical method based on the shear stress transfer (SST) k-ω two-path turbulence model. The computations are performed with the commercial CFD solver FLUENT 13.0 code. The interference characteristics of the array jets are analyzed, the influence laws of the microslit array mode and the angle of attack on drag reduction performance are explored, and a prediction method of passivation leading edge drag characteristics based on radial basis function (RBF) neural network is constructed. The research conditions are as follows: the incoming Mach number is 2.0, the angle of attack ranges from 0° to 30°, and the number of microslits is 0 to 5. The results show that when there is interference between microslit jets, the interaction between adjacent reverse reflux regions will change the shape of the reflux regions. When there is a microslit jet in the center line, the position of the detached shock wave is more affected by the angle of attack. The drag characteristics of the leading edge are determined by the location of the detached shock wave and the characteristics of the reflux regions. The mode of microslits determines the drag reduction efficiency and sensitivity to the angle of attack. There may be contradictions in the design of array microslit-opposed jet schemes regarding the overall drag reduction efficiency, local load, and drag reduction stability. The drag prediction model based on the RBF neural network has an accuracy of 5%, which can provide support for the design of array microslit-opposed jets. Practical Applications: The array microslit-opposed jets provide a new technical approach for reducing drag on the passivation leading edge. The paper studies its flow characteristics and laws and provides relevant conclusions. It can serve as a theoretical reference during design. The number of microslits is not the more the better. When designing microslit patterns, many factors need to be considered. [ABSTRACT FROM AUTHOR]