Numerical simulation of feedback flutter control for a single-box-girder suspension bridge by twin-winglet system

Through numerical simulation investigation, a twin-winglet system is used as an aerodynamic affiliated facility to increase the flutter stability of a box-girder suspension bridge. Its flutter suppression effect can be greatly enhanced when the winglet rotation is feedback-controlled in real-time, depending on the deck motion. Since the control algorithm was previously examined by a self-consistent mathematical model, the control process is realized through computational fluid dynamics simulation in this paper to check the applicability of the device. Moreover, the non-interference assumption used in the control algorithm is analyzed carefully, with several cases of different distance between a deck and winglets. The results verify the effectiveness and robustness of the control algorithm, and also provide a quantitative conclusion about the influence effect, which can be used in the design of a twin-winglet system. In addition, the advantages of this twin-winglet facility are revealed by investigations of the flutter control mechanism.