Progress of the Identification of Noise Sources and Analysis of Noise Source Mechanisms in Jets

Abstract

Jet noise is the dominating component of aircraft aerodynamic noise, and causes severe environmental pollution and health threats. Yet lack of a fundamental understanding of how turbulent eddies generate noise radiation poses great challenges in designing accurate noise prediction methodologies and efficient noise reduction devices. The progresses and limitations of the studies on the turbulent noise source identification and noise source mechanisms in open literature are reviewed. Judging by the cause-effect reasoning that the turbulent fluctuations generate acoustic perturbations, it seems promising to develop physically more accurate models and governing equations to separate the acoustic and turbulent fluctuations in future research. By explicitly formulating the former as the generalized function of the latter, the dynamic process how turbulent eddies generate noise radiations is revealed.

Keywords

• aerodynamic noise
• jet noise
• noise source identification
• source mechanism analysis