加装涡流发生器有助于大型风力机叶片根部部位厚翼型表面边界层气流分离的控制。以安装涡流发生器的DU-W2-250叶片段为研究对象,采用?-Reθt转捩模型和SST湍流模型,从叶片表面的摩阻系数、法向速度型以及压力分布规律3个方面进行气动特性分析和比较,并与Delft的试验数据对比。研究结果表明转捩模型计算结果与试验值更加吻合,湍流模型的升力系数最大误差达21.3%,升阻比最大误差达51.8%。转捩模型可以准确捕捉叶片的转捩现象,在小迎角下转捩点发生在VGs下游,随着迎角增大转捩点向VGs上游过渡。在转捩效应的影响下,叶片近壁面流体具有高能量而使流速更高。转捩模型计算得到的叶片上表面压力系数高于湍流模型,在20°大攻角下更加明显。
In the inboard of blade of the huge wind turbine,the air separation often took place because of the thick aerofoil.Vortex generators(VGs) is an effective way of controlling the air separation.The DU-W2-250 aerofoil with the vortex generators was researched.The ?-Reθt transition model and the SST turbulent model were used to investigate the aerodynamics in aspect of the rules of the friction coefficient,the velocity structure and the pressure distribution of blade surface.The results obtained from the two models mentioned above were compared.The results show that the transition model results have well agreement with test results.However,the maximum error of lift coefficient and the lift-drag ratio of SST model are 21.3% and 51.8% respectively.The transition model is able to obtain the transition point of blade surface,which occurs in the downstream of VGs in small attack angle and gradually transports to the upper-stream of VGs with the attack angle growing.Under the effect of the VGs and the transition,the airflow has higher velocity near the surface of blade than that far away from the surface of blade because the airflow has high energy.The pressure coefficient of upper-surface of transition model is higher than that of SST model,which is more obvious in bigger attack angle,for example 20° attack angle.