Aeroacoustic Analysis and Geometric Tuning Of Nozzle Tabs for Advanced Jet Noise Control In Aviation Propulsion Systems

Abstract

Jet noise generated from high-speed exhaust flows is a major concern in modern aviation due to environmental and regulatory constraints. This study focuses on aeroacoustic analysis and geometric optimization of nozzle tab configurations to reduce jet noise while maintaining aerodynamic performance. A baseline convergent nozzle and modified tabbed configurations with ±5 mm penetration was designed and analyzed using Computational Fluid Dynamics (CFD) in ANSYS CFX. The study evaluates flow characteristics such as velocity distribution, pressure variation, temperature decay, and Mach number contours to understand mixing enhancement and noise reduction mechanisms. Results indicate that geometric tuning significantly affects shear-layer development, potential core length, and turbulence intensity. Increased mixing due to optimized tab geometry leads to faster jet decay and reduced shock-cell structures, which are responsible for broadband shock-associated noise. The findings demonstrate that passive control through nozzle tab modification is an effective method for improving aeroacoustic performance with minimal thrust penalty.