Aerodynamic Force and Moment on Oscillating Airfoils in Cascade

A systematic theory is developed for airfoils in cascade oscillating about their mean position with constant interblade phase angle in a uniform incompressible flow. The theory fully accounts for the effect of angle of attack of the mean flow, the airfoils’ thickness and camber, and the cascade solidity and stagger. The formulation leads to two singular integral equations in the complex plane which are solved numerically by collocation. The results show that for certain values of the interblade phase angle, the airfoils’ thickness and incidence have a significant influence on the unsteady lift and moment particularly for staggered cascades.