Numerical Study of Flow Control to Increase Vertical Tail Effectiveness of an Aircraft by Tangential Blowing

This paper aims to utilize blowing as an active flow control technology to enhance the aerodynamic efficiency of an aircraft's vertical tail. A computational method has been developed to increase the aerodynamic performance of the vertical tail (at zero angle of attack and zero side slip conditions) through tangential blowing at Mach 0.2. The use of blowing for increased directional control has the potential to improve airplane performance and reduce fuel consumption. The numerical approach relies on the Reynolds averaged Navier-Stokes formulation for grids. A computational analysis examines three geometry types aimed at enhancing the side force. The initial form, or base state, has no tangential blowing, whereas the second uses tangential blowing from a full span slot and the third applies blowing from a series of discrete slots at the hinge line. In the second scenario, separation is entirely regulated, whereas control for discrete slots is comparatively weaker. The side force increased by 8.5% in the condition where 9.9 kg/s of air was blown through a single slot compared to the base condition. Meanwhile, when air is blown through discrete slots at a mass flow rate of 2.7 kg/s, there is a 4% increase in side force. A comparison of utilizing two methods, one with single slot and the other with discrete slots, reveals that the latter requires 70% less mass flow rate to achieve identical side force as the former.