仿生翅室对跨声速扩压叶栅角区分离流动影响研究

Effects of Bionic Chamber on Corner Separation Flow in a Transonic Compressor Cascade

关键词:  航空发动机  压气机  叶片  叶栅  角区分离  数值模拟  流动控制

Key words:  Aeroengine  Compressor  Blade  Cascade  Corner separation  Numerical simulation  Flow control

摘要:

为了抑制压气机叶片吸力面角区分离，减小内部流动损失，改善通道内的通流能力，基于蜻蜓翅翼的翅室和褶皱结构特征，在跨声速扩压叶栅的端壁上布置仿生翅室结构。采用数值模拟方法，研究不同深度的仿生翅室结构对角区分离流动的影响。研究结果表明：0°攻角条件下仿生翅室影响效果最明显，能够提高端壁附近的湍动能，增加靠近端壁处流体速度，减小分离涡的影响范围，增强叶栅通流能力，从而提高叶片的扩压能力；随着深度的增加，对角区分离的抑制效果先增加后减小，最佳方案使得总压损失系数降低7.22%。当攻角小于最小损失攻角，仿生翅室诱导分离涡起始点提前，扩大角区分离范围，增加了流动损失；当攻角大于最小损失攻角，对角区分离的抑制效果先增强后减弱，角区分离范围大到一定程度后，其产生的效果不明显。

Abstract:

In order to restrain the corner separation on suction surface， reduce the flow loss and improve the flow capacity of the compressor stator passage， bionic chamber structure is applied. This structure， based on the wing chamber and wrinkled structure of dragonfly wings， is setted on the endwall of a transonic compressor cascade. The effects of bionic chamber with different depth on the corner separation were studied by numerical simulation. The results show that the most obvious effect occurs when the incidence angle is 0°. The turbulent kinetic energy and the flow rate near the endwall can be enhanced. The influence range of separation vortex is reduced， the flow capacity of cascade is enhanced， and the diffusion capacity is improved. With the increase of depth， the restraining effect of bionic chamber on corner separation first decreases and then increases. The total pressure loss coefficient of the optimal scheme is reduced by 7.22%. When the incidence angle is less than the minimum loss incidence angle， the starting point of separation vortex is advanced due to the induction of bionic chamber， which expands the separation range and enhances the separation loss in corner region. While the incidence angle is greater than the minimum loss incidence angle， the restraining effect of corner separation first increases and then decreases. Especially when the corner separation is large to a certain extent， there is no obvious effect.