Abstract:
The concept of a close canard wing is proposed in the first part of this paper for improving the poor performance of the Low-speed Blended-wing-body (BWB) in longitudinal control and trim. For different positions and shapes of the canard, the aerodynamic performance is investigated respectively by numerical simulation, and the flow mechanism that effect the lift and moment of the BWB configuration is analyzed. The result shows that, for the BWB configuration, the canard can keep the canard vortex stable with high intensity after the vortex core of the BWB inner wing breakdowns at high attack angle, leading to the increment of the stall angle of BWB configuration, so that a higher lift and pitch up control capability can be achieved. The result also shows that the improvement of aerodynamic efficiency has a close relationship with the position and geometry of the canard. A sweep back canard with a high position and short distance can produce favorable interference with the BWB wing, which is helpful to advance the longitudinal control and trim capability. The results of the article can provide certain theoretical references for the advanced research and development of the BWB configuration in the future commercial study.