Experimental Study of Vertical Tail Model Flow Control Based on Oscillating Jet

In this paper, wind tunnel experiments are conducted to study the control law and mechanism of oscillating jet flow control to improve the aerodynamic characteristics of the vertical tail when a civil aircraft encounters left side gust or significant crosswind during takeoff and landing. We measured the vertical tail scaling model's aerodynamics, spatial flow field, and surface pressure when the Reynolds number was 2.12 x 10(5). The maximum momentum coefficient of the oscillating jet actuator reaches 0.332%. In addition, we studied the flow control effect of the three-dimensional vertical tail scaled model in different spanwise positions. The experimental results show that the oscillating jet at the rear edge of the stabilizer can significantly increase the lateral force of the vertical tail, and the increment of the lateral force can reach 36.5% under the worst condition of the negative side slip angle of the vertical tail. We can improve the lateral force coefficient of the vertical tail model by applying flow control alone at different spanwise locations. The wing root's control effect and the vertical tail's middle section are better than the wing tip's. The oscillating jet can effectively restrain the flow separation on the rudder. In addition, the input of a high-energy jet "ejects" the mainstream, which increases the flow velocity at the side of the vertical tail actuator. It increases the circulation of the vertical tail. The oscillating jet flow control technology can effectively improve the vertical tail's steering efficiency and increase the vertical tail's lateral force, which is of great significance in improving the safety and economy of civil aircraft.