变弯度导叶铰接位置对风扇振动特性的影响

For the rotor blade resonance induced by the wake excitation of variable inlet guide vanes，forced vibration analysis of the fan rotor was conducted with the utilization of the harmonic response method. The effects of variable inlet guide vane at different hinge positions on the aerodynamic performance and vibration characteristics of the downstream rotor blade were studied. Results indicate that as the hinge position moves towards the trailing edge，the mass flow rate，pressure ratio，and efficiency of the fan rotor increase，while the stability margin decreases，which mainly affects the inlet angle of the downstream rotor blade root. For aerodynamic excitation，as the hinge position moves backward，the pressure amplitude of the rotor blade increases and the phase changes sharply. By converting the unsteady aerodynamic excitation into the modal space，it can be seen that the modal aerodynamic force reaches the maximum value at the hinge position of 35%C（C is the axial chord length），and then decreases to the minimum value before increasing，which is consistent with the variation law of vibration response. The hinge position of the guide vane has little effect on the aerodynamic damping of the higher-order local modes of concern，with a maximum difference of 0.046%. In terms of vibration response，the vibration stress of rotor blade varies sharply with the hinge position and is non-monotonic. It is the smallest at the design position，and reaches 15 times of the design position at 35%C. For the model and operating conditions studied in this article，the optimal hinge position is 45%C，which is different from the 25%C when only considering the impact of aerodynamic performance. Therefore，in the design of variable inlet guide vanes，it is necessary to consider their impact on the vibration characteristics.