Numerical Investigations on Characteristic of Fan Based on Two-Way Fluid-Structure Interaction Approach

There is strong coupling between the long fan blades and the fluid in actual flow field, because the fan rotor works in the high pressure ratio, high rotation speed and high load level environment. In this paper, the fluid-structure interaction (FSI) problem of the fan rotor is solved by two-way fluid-structure interaction method based on the time marching, and the supersonic unstalled flutter phenomenon of the fan rotor is studied. The numerical results show that the fan rotor characteristic line shift 0.7% towards the large flow direction, the efficiency is reduced 0.76%, the total pressure ratio remains the same and the stable operation margin decreases slightly when the coupling influence is considered. The supersonic unstalled flutter based on the first-order natural mode vibration of the blade may occur near the maximum efficiency point at the design speed of the fan rotor.