复杂三维气动布局在高负荷压气机中应用的数值模拟

Application of Complex 3D Aerodynamic Layout in Highly Loaded Compressor on Numerical Simulation

为了充分发挥主被动控制技术融合的复杂气动布局在高负荷压气机中的应用潜力,通过数值模拟的方式,设计了多台采用不同气动布局方式的单级高负荷压气机进行对比研究。研究结果表明,在静叶中融合应用三维叶片造型技术时,端弯叶片前缘所呈现的反弯形态会导致静叶损失增加,但端部气流角更好的匹配保证了压气机失速裕度的提高。在端弯叶片设计基础之上叠加应用正弯造型可以抵消由于端弯而导致的前缘反弯形态,并有效降低总压损失,进一步提高失速裕度。通过调节进口预旋,动叶的逆压梯度降低,效率得到较大幅度的提升。此时静叶将承担更多的静压升,可以通过叠加应用附面层抽吸技术来保证静叶的正常工作。在正弯曲造型的静叶栅中叠加应用仅在吸力面角区抽吸的主动流动控制结构,在负攻角的来流条件下,分离流动控制效果相对不明显。

In order to reach its full application potential of complex 3D aerodynamic layouts integrating active and passive flow control technologies, by numerical simulation, several single-stage highly loaded compressors adopting different aerodynamic layouts have been designed for a comparative study. The results show that, when integrating 3D blade techniques in stators, the leading edge of the re-camber blade appears like a negative-bowed blade which makes the lose increase, while the better match of the flow angle near the endwalls ensures the improvement of stall margin. Based on the re-camber blade design, a superimposed positive-bowed blade can offset the negative-bowed appearance of the leading-edge, reduce the total pressure loss effectively, and improve the stall margin furtherly. By adjusting an inlet prewhirl, adverse pressure gradient decreases in the rotor, to increase rotor＇s efficiency by a large margin. Meanwhile, the stator undertake more pressure rise, and the superimposed boundary layer suction can guarantee the stator functioning properly. By adopting the superimposed boundary layer suction only in the comer region of a positive-bowed blade, while the inlet incidence of stator is negative, 3D aerodynamic layout lacks of effective control of the separation flow.