Method to predict the blade vibration stress induced by wake flow

This paper aims at researching the influence of the wake flow from the stator vanes of the previous stage acting on the following rotor blades.The wake flow of stator vanes and the unsteady flow in the passage of rotor blades were solved by using oscillating fluid mechanics theory and parametric polynomial method.Then the aerodynamic pressure field obtained from the analysis of unsteady aerodynamics was transformed to the form of load pressure field which is suitable to the analysis of structure dynamics.The damping coefficient of response applied to the analysis was achieved from the experimental result.Thus,the response of each harmonic can be calculated first,and then the whole response can be achieved by superimposing the responses of all harmonics.From solving the flow fluid to solving the structure response,a semi-empirical method for engineering application was established to predict the vibration stress of blades induced by wake flow.