Numerical investigation on synthetic jet flow control inside an S-inlet duct

合成射流改善s形进气道流场特性的研究

“…. 由于采用的几何模型关于 Z=0 完全对称, 来流条件也完全对称, 根据理论及实 际结果分析 [17,18] , 流场对称, 为了节约计算资源采用 半模计算, 选择流场的 Z 为负值的半边, 文中所有的 边界层内速度低于核心区, 所以流线具有较小 的曲率半径, 因而会向内侧折转, 出现由弯道外侧向 内侧的横向流动, 而进气道靠近下壁面的流体在离 心力的作用下向上侧运动, 形成二次涡 [19] . 在图 4(a) 中 x/D=0.…”

Effects of flow control in the presence of asymmetric inflows in twin air-intake

“…Various flow control techniques have been used to manage flow separation and to improve the aerodynamic performance of different air-intake ducts. Vortex generator array (Paul et al, 2013a) and vortex generator jets (Paul et al, 2013b) and synthetic jets (Chen and Wang, 2012;Kim et al, 2016;Wojewodka et al, 2018) are notable among them. For high offset diffusing ducts, Burrows et al (2019) successfully used trapped vorticity technique to reduce the flow distortion coefficient in diffusing duct having offset.…”

“…However, with the effective use of flow control technique, the flow separation and flow reversal are suppressed as evident from Figure4(b). Flow also became more uniform in controlled cases.5.2 Secondary flowThe secondary flow in uncontrolled transitional air-intake will enhance the flow separation(Chen and Wang, 2012). This flow separation combined with secondary flow vortices manifests in low static pressure recovery and non-uniformity of the flow at the AIP of twin air-intake duct.…”

A review of flow control techniques and optimisation in s-shaped ducts

“…Due to the curvature in the duct, the incoming air is slowed down much faster than in conventional straight ducts which leads to shorter designs and considerable weight savings [1,2]. It is estimated that the net weight of an aircraft would decrease by 15% if the length of the fuselage is reduced by one inlet diameter [3]. Moreover, the curved inlet is a line-of-sight blockage to the engine fan/compressor and thus effectively lowers the noise level as well as radar and infrared signatures [1,3].…”