Abstract:
This Report gives a method for calculating the aerodynamic forces and moments acting on unstalled vibrating cascade blades. The forces and moments due to both bending and torsional vibration are calculated, and also due to wakes from periodic obstructions far upstream which move relative to the cascade in question. The calculation has been programmed for EDSAC II, the electronic computer at the Cambridge University Mathematical Laboratory, and the essential formulae are summarized in an Appendix, in order to facilitate the preparation of programmes for other machines. The Report includes skeleton tables of the force and moment coefficients for two space/chord ratios. The coefficients can be used to predict the occurrence of pure torsional or coupled flutter and the vibration induced by periodic disturbance in the flow.
