Effect of canard-chordwise blowing on the aerodynamic characteristics of blended wing body aircraft

鸭翼弦向吹气对BWB飞机气动特性的影响

¹ Beijing Aircraft Technology Research Institute, Commercial Aircraft Corporation of China, Beijing 102211, China
² School of Astronautics, Harbin Institute of Technology, Harbin 150001, China

Received: 16 November 2023

Abstract

To enhance the effect of the canard increasing lift and pitching moment coefficient of the blended-wing-body(BWB) aircraft, numerical simulation is adopted to analyze the effect of the canard-chordwise blowing on the low-speed aerodynamic characteristics of BWB configuration. By presenting the results of blowing momentum coefficient at different angles of attack, the flow mechanism of chordwise blowing device's influence on the lift and pitching moment coefficient is analyzed, followed by investigating the effect of the blowing momentum coefficient and chordwise blowing position on the low-speed aerodynamic characteristics. The numerical simulation results show that by arranging a chordwise blowing device on the upper surface of the canard, the flow pattern of canard can be significantly improved, enlarging negative pressure region on the upper surface of canard and increasing the peak negative pressure, resulting in an increase in lift coefficient of the canard and a decrease on the difficulty of the longitudinal trimming and maneuvering in the takeoff and landing of the BWB aircraft. Increasing the blowing momentum coefficient produces more favorable interference. As the chordwise blowing position moves backwards, the canard and the whole aircraft lift coefficient increases gradually and then decreases, where an optimal range of chordwise blowing position can be reached. The results of the article show that the chordwise blowing device directly improves the flow field of the canard and increases the lift and pitching moment coefficient, which provides theoretical support for the advanced research of BWB configuration aircraft.

摘要

为更好发挥鸭翼的增升抬头效果, 对采用鸭翼上表面弦向吹气技术的翼身融合(blended-wing-body, BWB)布局飞机开展计算分析, 给出不同迎角及吹气动量系数下的数值模拟结果, 分析了鸭翼弦向吹气对BWB飞机的流动影响机理, 研究了吹气动量系数及弦向吹气位置对全机低速气动特性的影响。吹气前后的计算结果表明, 通过在鸭翼上表面布置弦向吹气装置, 可显著改变鸭翼表面流动形态, 扩大鸭翼上表面负压区域, 增大负压峰值, 从而提高鸭翼升力, 降低BWB飞机低速起降的配平和抬头操纵难度, 且吹气动量系数越高, 增升抬头效果越明显。随着吹气弦向位置向后移动, 鸭翼及全机升力系数逐渐增加然后降低, 存在一个最佳的弦向吹气位置范围。该技术可直接改善飞机流场, 起到增升抬头的作用, 对BWB飞机的发展和工程应用具有一定的理论参考价值。