为减小离心风机转子与蜗舌之间的动静干涉噪声，提出一种弧形蜗舌结构，并分析了其对离心风机噪声的影响机制。在现有风机模型基础上，设计了半径为R100、R50和R23的弧形蜗舌代替原蜗舌，采用大涡模拟获取流场信息，利用LMS Virtual.lab间接边界元方法，分析离心风机动静干涉噪声。结果表明:弧形蜗舌有助于减缓蜗舌前缘处流体的冲击脉动速度，能更好地调控蜗壳回流流场，减小气流在蜗壳壁面上附面层的流动分离，改变气流激振力引起的蜗壳振动噪声及动静干涉噪声；弧形蜗舌结构降低了蜗壳表面的压力脉动幅值，噪声整体表现为宽频特性，能量集中在中低频，R50风机噪声表现最优，总声压级最大可降低3 dB。

In order to reduce the dynamic and static interference noise between the rotor and the volute tongue of centrifugal fan, an arc-shaped volute structure was proposed to investigate its effect mechanism on the centrifugal fan noise. On the basis of the existing fan model, the arcshaped volute tongue with radius of R100, R50 and R23 is designed to replace the original volute tongue. The flow field information is obtained by large eddy simulation. The fluid structure noise coupling simulation of centrifugal fan is carried out by using LMS Virtual.lab indirect boundary element method, and the dynamic and static interference noise of centrifugal fan is analyzed. The results show that the curved volute helps to reduce the impact pulse velocity of the fluid at the leading edge of the volute It can better control the return flow field of the volute, reduce the flow separation of the surface layer of the volute on the wall surface of the volute, and change the vibration noise and dynamic interference noise of the volute caused by the airflow excitation force. The curved volute structure reduces the pressure pulsation amplitude on the surface of the volute. The overall performance is a broadband feature, the energy is concentrated in the low and medium frequencies, and the total sound pressure level can be reduced by up to 3 dB.

TK83

国家自然科学基金（51106099,50976072）；上海市科委科研基金（13DZ2260900）