关键词: 振动与波, 离心通风机, 蜗舌, 压力脉动, 数值模拟

Abstract:

Worm tongue is an important component of the centrifugal ventilator. To investigate its influences on the vibration noise of the centrifugal ventilator, numerical simulation is conducted for the aerodynamic actuation of a certain centrifugal ventilator. Through steady computation, it is found that the structure improvement can help to reduce local vortex, which is an important factor contributing to vibration. Through unsteady simulation, it is verified that the impact of the worm tongue structure on the aerodynamic actuation is mainly featured by the amelioration of local pressure fluctuation, especially the decrease of the fluctuation at blade frequency intrigued by the outflow from impeller. Based on the numerical results for the model machine, evaluation on the variation of the vibration noise is made. The results show that improvement of the worm tongue structure is beneficial to the reduction of the vibration noise; Numerical analysis for aerodynamic actuation can provide judgments to evaluate the effectiveness of the low-noise improvement of the ventilator.