导航

ACTA AERONAUTICAET ASTRONAUTICA SINICA ›› 2022, Vol. 43 ›› Issue (1): 124931.doi: 10.7527/S1000-6893.2020.24931

• Fluid Mechanics and Flight Mechanics • Previous Articles     Next Articles

Longitudinal stability of blended-wing-body aircraft based on experimental bifurcation analysis

FU Junquan1, SHI Zhiwei1, GENG Xi1, ZHU Jiachen1, WANG Lishuang1, WU Dawei2, PAN Lijun2   

  1. 1. College of Aerospace Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China;
    2. COMAC Shanghai Aircraft Design and Research Institute, Shanghai 201210, China
  • Received:2020-10-30 Revised:2020-12-15 Online:2022-01-15 Published:2020-12-14
  • Supported by:
    National Natural Science Foundation of China (12072155); Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions; Key Laboratory of Unsteady Aerodynamics and Flow Control, Ministry of Industry and Information Technology

Abstract: Bifurcation analysis and the catastrophe theory are used to study the longitudinal stability of Blended-Wing-Body (BWB) aircraft. Equilibrium branches of the angle of attack with the elevator are obtained, and stability of the branches and the catastrophe points analyzed. Then bifurcation analysis is introduced into the virtual flight tests to physically track the equilibrium branches, enabling the experimental bifurcation analysis research in the wind tunnel. A pseudo-linear controller based on the nonlinear dynamic inverse is designed, with the open-loop and closed-loop experimental bifurcation diagrams obtained and analyzed. The comparative analysis shows that the theoretical bifurcation analysis and the open-loop experimental bifurcation analysis are basically consistent in the range of small angles of attack, verifying the feasibility and accuracy of the experimental bifurcation analysis method. The longitudinal instability of the BWB aircraft is mainly caused by the sudden changes of C. The closed-loop experimental bifurcation analysis realizes the nonlinear global stability control, transforming the unstable equilibrium branch into a stable one through the longitudinal nonlinear controller.

Key words: Blended-Wing-Body (BWB), longitudinal stability, experimental bifurcation analysis, virtual flight tests, nonlinear dynamic inversion

CLC Number: