Numerical Investigation of Unsteady Aerodynamic Characteristics and Shock Behaviour of A Pitch Oscillating Transonic Cascade

摘要

A numerical study based on the thin layer Navier-Stokes equations was carried out on the pitch oscillating two-dimensional transonic cascade with the axis at midchord. The Baldwin-Lomax turbulence model was used to simulate the effects of turbulence. A double-circular arc airfoil with 5percent thickness is used. The unsteady aerodynamic characteristics and the role of shock behaviour were investigated. The results indicate that the shock movement acts as an aerodynamically unstable factor at the high reduced frequency and with degree of interblade phase angle of 180 degree. However the pitch oscillating transonic cascade remains aerodynamically stable in the range of calculations. On the other hand, it becomes unstable if the pitching axis is located in front of x/c = 0.37.