Study of Different Designs of Chevrons for Effective Noise Reduction in Jet Engines 2024-26-0408

Due to their remarkable efficiency and efficacy, chevrons have emerged as a prominent subject of investigation within the Aviation Industry, primarily aimed at mitigating aircraft noise levels and achieving a quieter airborne experience. Extensive research has identified the engine as the primary source of noise in aircraft, prompting the implementation of chevrons within the engine nozzle. These chevrons function by inducing streamwise vortices into the shear layer, thereby augmenting the mixing process and resulting in a noteworthy reduction of low-frequency noise emissions. Our paper aims to conduct a comparative computational analysis encompassing seven distinct chevron designs and a design without chevrons. The size and configuration of the chevrons with the jet engine nacelle were designed to match the nozzle diameter of 100.48mm and 56.76mm, utilizing the advanced SolidWorks CAD modeling software. Subsequently, the computational analysis for each design was carried out using the SolidWorks Flow Simulation software. When it comes to civilian aircraft, we can state that the noise emitted in case of landing and take-off is comparatively high, so the parameters considered to solve the model were taken accordingly. The results were obtained in the form of acoustic power level contour and turbulent energy contours which unambiguously exhibits the effectiveness of each of the chevron designs that were taken into consideration for study. The acquired solutions were finally used to run a comparative study among the designs. The obtained results unequivocally demonstrated that the incorporation of chevrons consistently led to a reduction in sound pressure levels across all cases. Notably, the round-shaped chevron design exhibited superior performance compared to the other designs, boasting a substantial noise reduction of 5.4%.