等离子体气动激励抑制高负荷压气机叶栅流动分离的实验研究

Experimental Investigation of Flow Separation Control on Highly Loaded Compressor Cascade by Plasma Aerodynamic Actuation

为揭示等离子体气动激励抑制高负荷压气机叶栅流动分离的作用效果和主要影响因素,在不同流场和激励条件下开展了等离子体流动控制的实验研究,介绍介质阻挡放电等离子体的产生原理与放电图像,利用栅后压力分布分析研究叶栅内部流场结构以及等离子体激励的变化规律和主要影响因素。结果表明:等离子体气动激励抑制附面层流动分离的作用效果随气流速度的增大逐渐下降,在攻角为2°时最佳,然后随攻角的增大激励效果显著下降;激励器电极的放电位置至关重要,在靠近角区分离线的起点时的激励效果明显强于其他位置;对等离子体气动激励的作用方式进行优化,变定常激励为非定常激励,使其与分离区的时间尺度实现最佳的耦合,是提高等离子体流动控制效果的一个重要途径。

To discover the mechanism and main influential factors of flow separation control on highly loaded compressor cascade by plasma aerodynamic actuation,the plasma flow control at different flow field and actuation conditions was experimentally studied.The dielectric barrier discharge plasma generation and image were presented.The cascade flowfield structure as well as the plasma actuation variation rule and impact factors were discussed and studied with pressure distribution behind blade trailing edge.Results show that actuation effects reduce with the increase of airflow velocity and incidence angle,but become the best at i= 2°;the location of actuator electrodes is of vital importance,the best is in slight front of place where separation line starts.Turning steady actuation to unsteady actuation to optimize the actuation mode can reach coupling of time scale between unsteady actuation and separation region,which is an important mean of enhancing the plasma flow control effect.