大型低速翼型风洞侧壁边界层控制系统研制

The development of sidewall boundary layer control system for large airfoil low-speed wind tunnel

介绍了NF-3大型低速翼型风洞多喷嘴级联吹气侧壁边界层控制系统的结构和原理。为验证本系统的功能和性能,采用侧壁吹气方案并使用增量式PID控制算法进行气源压力的控制,对具有增升装置的GAW-1翼型进行了侧壁边界层吹除试验研究。试验结果表明:(1)使用侧壁吹气系统后翼型模型中间截面最大升力系数由2.79增加到2.84,增加幅度1.8%,且模型端面截面的升力系数与中间截面的升力系数基本上相等;(2)利用增量式PID控制算法对气源压力的精确控制较好地完成了风洞侧壁吹气功能,改善了翼型表面流动,减小了侧壁边界层对翼型试验结果的影响。

This paper describes the structure and the application of multi-injector blowing sidewall boundary layer control system for NF 3 large airfoil low-speed wind tunnel. The sidewall boundary layer blowing experimental investigation of GAW-1 airfoil with high lift device by using the method of sidewall blowing and applying incremental PID control algorithm to control the pneumatic pressure is carried out for testing the function and performance of the system. The re- sults show that the highest lift coefficient increases by 1.8~ from 2.79 to 2.84 on the middle sec- tion of the airfoil, and the lift coefficient of the edge tion. It shows that the system applying incremental section is basically equal to the middle sec PID control algorithm to control the pneu matic pressure accurately has achieved the function of wind tunnel sidewall boundary layer blo wing. Sidewall blowing improves the flow on the surface of airfoil and decreases the effect of side wall boundary layer on the airfoil experiment results.