Flow topology and noise modeling of trailing edge serrations

Abstract

Trailing edge serrations (TESs) have been extensively recognized in the area of wind turbines and aviation, capable of noticeably reducing the turbulent trailing edge noise. Plenty of researchers have achieved the simulation of the airfoil with the serrated trailing edge to delve into its potential and mechanism to reduce noise, whereas the thin and sharp structure of the serrations imposes huge difficulties on successful simulation. Thus, a novel modeling method was proposed in this study to replicate the hydrodynamic and acoustic features of the serrations. The effect of serrations on the flow field was affected by the geometrical features and flow parameters of serrations, as achieved by substituting the momentum source into the N-S equation. The LES simulation coupled with FW-H integration was performed to generate the flow field and far field sound pressure, respectively. As suggested in the results, the hydrodynamic and aeroacoustic results of modeled airfoil were well consistent with the solid serrations. Given the mentioned results, the relevant noise reduction mechanism was elucidated in detail.