Simulation of Flow-Induced Noise Generation on Orifice Plates in an Aircraft Climate Control System

The noise generated by a valve placed in the pipeline of an aircraft climate control system was investigated with two approaches based on Lighthill's analogy, one is the variational formulation of the Lighthill's analogy implemented in a Finite Element framework, the other is the so-called porous Ffowcs Williams-Hawkings (KFW-H) formulation. The finite volume method is used to obtain the fluctuating pressure data, the radiation noise of the valve is obtained by integrating the FW-H equation method and the acoustic finite element hybrid method.The effects of flow velocity, valve opening, valve position, pipe diameter and temperature on the sound pressure lever were studied respectively.The result show: air flowing produced a pressure difference between the front and rear valve, which generate vortex and produces strong aerodynamic noise. the calculation results of the KFW-H on the whole frequency are less than CFD mixed acoustic finite element method Because miss of the influence of structure on the noise.The valve opening and flow speed will significantly affect the aerodynamic noise of the pipeline.The use of circular arc valve plate instead of butterfly valve plate can achieve good noise reduction effect.