Shock Associated Noise Generation in Curved Turbulent Coanda Wall Jets

• Main Authors: Lubert, Caroline, Shafer, Richard J.
• Format: Conference Proceeding
• Language: English
• ISSN: 1939-800X
• DOI: 10.1121/1.3675530

Curved three-dimensional turbulent Coanda wall jets are present in a multitude of natural and engineering applications. The mechanism by which they form a shock-cell structure is poorly understood, as is the accompanying shock-associated noise (SAN) generation. This paper discusses these phenomena from both a modeling and experimental perspective. The Method of Characteristics is used to rewrite the governing hyperbolic partial differential equations as ordinary differential equations, which are then solved numerically using the Euler predictor-corrector method. The effects of complicating factors -- such as radial expansion and streamline curvature -- on the prediction of shock-cell location are then discussed. This paper next compares the theoretical calculations of the shock-wave structure with associated schlieren flow visualization results. Related acoustical measurements are also addressed. In this way, critical flow characteristics for shock-cell formation are identified, and their influence on SAN discussed.