Dynamics simulation research on fault conditions of deflecting to airflow flap mechanism of civil aircraft

Abstract

The deflecting to airflow flap of civil aircraft are generally driven by complex multi-hinge mechanisms in space. According to the requirements of the airworthiness clause CCAR25.671, it is necessary to carry out research on the mechanism characteristics under typical faults. Firstly, a digital prototype of the mechanism motion is constructed, and the hinge point of the rigid multi-hinge mechanism is associated with the flexible flap body by using the RBE2 unit, and the rigid-flexible coupling dynamic model of the flap mechanism is established. Then, under three aerodynamic load conditions of cruise, take-off and landing, two typical faults, hinge jamming and one-side failure of control system, are simulated by adjusting the hinge friction coefficient and setting one-side driving failure. Finally, the variation law of driving torque and hinge point load is analyzed. The results show that:when the hinge is stuck, the inner drive link ear piece is stretched and damaged; when the inner drive fails, the radial load at the hinge point of the outer rocker arm increases significantly. In practice, we should focus on the middle joint of the outer rocker arm of this type of flap. The radial and axial load-bearing capacity of the bearing avoids the situation of separate manipulation of the outer mechanism, and at the same time, it is necessary to increase the torque protection for the entire drive system.

Keywords

• high-lift device
• rigid-fiexible coupling
• dynamic simulation
• fault simulation