射流襟翼对翼型气动特性影响研究

EFFECT OF JET FLAP ON AERODYNAMIC CHARACTERISTICS OF AIRFOIL

通过施加射流技术于翼型尾缘可有效提高风力机气动性能,达到与格尼襟翼相近的气动力提升效果。该文基于NACA0018翼型尾缘射流开展研究,采用计算流体动力学方法对比分析尾缘射流与传统格尼襟翼对其气动特性的影响,并考虑不同射流出口宽度对翼型气动性能提升效果。结果表明:尾缘射流可有效提升翼型气动性能,同时降低小攻角下的阻力系数,且随射流动量系数增加,降阻效果更明显;尾缘射流可有效降低格尼襟翼引入的阻力增量,提高翼型升阻比;当射流动量系数一定时,尾缘射流翼型升阻比与转矩系数随射流出口宽度增加而减小;当射流速度为常数时,随射流出口宽度增加,翼型气动特性有明显提高。

Through applying jet technology to the trailing edge of the airfoil,the aerodynamic performance of the wind turbine can be effectively improved,obtaining the similar effect with the Gurney flap in lift improvement.In this paper,based on the trailing edge jet of the NACA0018 airfoil.The comparison and the analysis on the aerodynamic performances,the effects of trailing edge jet and traditional Gurney flap on its aerodynamic characteristics are contrastively analyzed by the computational fluid dynamics(CFD)method.Moreover,the improvement effect of different jet outlet widths on aerodynamic performance of airfoil is considered.The results show that the trailing edge jet effectively improves the aerodynamic performance of the airfoil and reduce the drag coefficient at a small angle of attack.The drag reduction effect becomes more obvious with the increase of the momentum coefficient of the jet.And the trailing edge jet effectively reduce the drag increment introduced by gurney flaps and increase the lift-drag ratio of airfoil.When the jet momentum coefficient is constant,the lift-drag ratio and torque coefficient of the trailing edge jet airfoil decrease with the increase of the jet outlet width.When the jet velocity is constant,the aerodynamic characteristics of the airfoil are obviously improved with the increase of the jet outlet width.