An efficient coupled method of cascade flutter investigation based on reduced order model

Direct numerical simulation of fluid/structure interaction of entire blade row is computation-intensive and time-consuming, this paper presents an ROM (Reduced Order Model) based coupling method which provides a significant increase in efficiency of flutter analysis of turbomachinery. This method constructs the reduced order aerodynamic model of cascade with identification of unsteady aerodynamic force in time domain, and makes ROM coupled with cascade structural dynamic equation in state-space form to establish the aeroelastic model. Flutter characteristics of cascade of STCF4 are analyzed by solving eigenvalues of the aeroelastic model. The results are compared by those of direct coupling method and uncoupled method and show good accuracy. ROM based coupling method improves computational efficiency by nearly two orders of magnitude compared to direct coupling method and uncoupled method based on solving Navier-Stokes equation directly.