不同结构的风管分流三通气动噪声分析
Analysis of aerodynamic noise of split tees of air ducts with different structures
摘要：
以空调系统风管分流三通为研究对象,采用Fluent和Actran联合仿真模拟的方法,探究了改变三通支管截面尺寸及支管曲率半径对三通气动噪声的影响。通过数值模拟的方法研究了三通的流场和声场特性,得到结论:三通支管气流不稳定,存在加速区和回流区,支管气动噪声声压级最大;速度分层、速度梯度和气体回流都会引起气体湍流运动从而导致涡的产生,引起脉动,这是三通产生气动噪声的主要原因;曲率半径分别为R、2R、3R和4R时,支管监测的最大声压级差能达到10.63 dB,选用4R曲率半径最合适。
Abstract：
This paper takes the split tee of air ducts in air conditioning systems as the research object, and uses the combined simulation method of Fluent and Actran to explore the influence of changing the cross-sectional dimension and curvature radius of the branch pipe on the aerodynamic noise of the tee. The flow field and sound field characteristics of the tee are studied through numerical simulation, and the results show that the airflow in the branch pipe of the tee is unstable, there are acceleration zones and recirculation zones, and the sound pressure level of aerodynamic noise of the branch pipe is the largest. Velocity stratification, velocity gradient and gas recirculation lead to gas turbulent motion, generating vortices and pulsations, which are the main reasons for the aerodynamic noise of the tee. When the curvature radius is R, 2R, 3R and 4R, respectively, the maximum sound pressure level difference monitored in the branch pipes can reach 10.63 dB, and the 4R curvature radius is the most suitable.
Keywords:tee; aerodynamic noise; air conditioning system; cross-sectional dimension; curvature radius; flow field; sound pressure level