Optimization of split drag rudder mechanism at different angles of attack in a flying wing airplane

In this research, the split drag system at different AOA for a flying wing aircraft has been simulated and optimized by a numerical method. The split drag system provides vertical axis control by creating asymmetric drag between the right and left wings. The aircraft under study is a lambda shape aircraft with a swept-back angle of 56. The split drag control system is made up of two surfaces on top of each other, by opening in the opposite direction on one side of the aircraft, it creates the drag necessary to produce yawing moment. Their installation position is at the tip of the wings and on the trailing edge. When using split drag, in addition to the yawing moment, a disturbing rolling moment is created, which is caused by the drag difference between the upper and lower surface of this system, and the reason for this is the change in the AOA of the aircraft. Asymmetric opening of the surfaces can reduce the induced roll to zero and in some cases to a minimum. The test was carried out in AOA of 0 to 12ᵒ for drag split opening angles of 10, 20, and 30ᵒ. Calculations based on equations (RANS) are discretized with the finite volume method. The obtained results show how much to add to the angle of the split drag surfaces depending on the AOA in order to find the most optimal mode to neutralize the roll, and finally, the optimized diagrams of this system are obtained.