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Updated: Mar 9, 2026
08:34
Visualization of High Speed Liquid Jet Impaction on a Moving Surface
Published on: April 17, 2015
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Scattering of turbulent-jet wavepackets by a swept trailing edge
Selene Piantanida1, Vincent Jaunet1, Jérôme Huber2
1Institute Pprime, 43 rue de l'Aérodrome, 86036 Poitiers, France.
The Journal of the Acoustical Society of America
|January 2, 2017
Summary
This study investigates installed jet noise using a simplified flat plate and round jet configuration. Findings reveal noise reduction with increased Mach number, sweep angle, and specific jet-plate distances, validated by predictive models.
Area of Science:
- Acoustics
- Aerodynamics
- Fluid Dynamics
Background:
- Installed jet noise is a significant concern in aerospace engineering.
- Understanding the interaction between jet flow and nearby surfaces is crucial for noise reduction.
Purpose of the Study:
- To investigate the effects of Mach number, jet-plate distance, and sweep angle on installed jet noise.
- To compare experimental measurements with predictions from kinematic wavepacket source models.
Main Methods:
- Acoustic measurements using an 18-microphone array on a cylindrical surface.
- Utilizing a simplified jet-plate configuration.
- Employing a kinematic wavepacket source model with both Transfer Function Green's Function (TGF) and boundary element method (BEM) computations.
Main Results:
- Scattered noise levels decrease with increasing Mach number.
- Scattered sound pressure level shows exponential dependence on jet-plate radial distance.
- Increasing trailing-edge sweep angle significantly reduces sideline noise and overall acoustic efficiency.
Conclusions:
- Experimental results show good agreement with model predictions.
- The kinematic wavepacket source models effectively capture essential sound generation mechanisms.
- The study validates low-cost prediction strategies for installed jet noise.
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