基于表面压力信息的空间流向涡识别方法

Spatial streamwise vortex signature identification based on surface pressure information

旋涡与表面的相互作用广泛存在于各类飞行器的绕流中,旋涡影响飞行器表面的压力分布,引起其气动特性的改变。而表面压力分布同样反映飞行器绕流中复杂涡系的空间流动特征,结合迎角、侧滑角等来流参数,可以判断飞行器受力状态和运动趋势。以平面点涡和“镜像涡”理论为基础,建立基于表面展向压力分布曲线的空间涡识别方法。根据截面展向压力分布曲线是否存在因主涡诱导下洗气流产生的正压区,定义流向旋涡的近物面流动和远物面流动;根据二次涡相对于主涡的位置,定义压力分布曲线的“近二次涡侧”和“远二次涡侧”。利用展向压力分布曲线“远二次涡侧”的1/4峰值、峰值及其展向位置,识别流向旋涡空间位置特征和强度特征。搭建涡-面相互作用试验平台,比较空间流场测量结果和表面压力信息识别结果,验证该方法有效性。研究结果表明:通过表面压力分布曲线可以辨识流向旋涡的空间位置和强度特征,空间流场测量与基于表面压力信息的旋涡识别结果的关联性分析验证了该方法的有效性。为重构飞行器周围旋涡流动结构,以及实现飞行器气动力的预测奠定了重要的技术基础。

The interaction between vortices and the object surface exists in various situations of aircraft.The vortices affect the pressure distribution on the surface and aerodynamic performance of the aircraft.The pressure distribution on the surface can reflect the spatial flow characteristics of the vortices around the aircraft.Combined with the angle of attack,sideslip angle and other flow parameters,the surface pressure distribution can predict the force state and motion trend of the aircraft.This study establishes a vortex signature identification method based on surface pressure distribution according to the theories of point vortex and“mirror vortex”.The experimental results demonstrate that the surface pressure distribution curve can characterize the spatial position(projection position and height of the vortex core distance surface)and intensity of the vortex.The correlation analysis between the spatial flow field measurement and the vortex identification result based on surface pressure distribution verifies the effectiveness of the proposed method.It has laid an important technical foundation for reconstructing the vortex flow structure around the aircraft and realizing the prediction of the aerodynamic forces of the aircraft.