Swirling-flow jet noise suppressors for aircraft engines

Schwartz, Ira R.

doi:10.2514/6.1976-508

3rd Aeroacoustics Conference 1976

DOI: 10.2514/6.1976-508

|View full text |Cite

Swirling-flow jet noise suppressors for aircraft engines

Ira R. Schwartz

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

2010

Publication Types

Select...

Article2

Relationship

Self Cite0

Independent2

Authors

Journals

Cited by 2 publications

(1 citation statement)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The magnitude of the effect of swirl increases with swirl angle. Jet noise suppression by swirling the jet flow was stimulated by Schwartz 6 who obtained a ratio of 3dB overall sound power reduction to 1% of thrust loss for a Pratt & Whitney JT15D-1 bypass flow engine by swirling a part of the primary flow. Lu et al 7 measured the noise and flow characteristics of model swirling jets and report that swirling jet noise is broadband in nature similar to non-swirling jet noise.…”

mentioning

confidence: 99%

Aeroacoustics of Drag-Generating Swirling Exhaust Flows

Shah¹,

Mobed²,

Spakovszky³

et al. 2010

AIAA Journal

View full text Add to dashboard Cite

Aircraft on approach in high-drag and high-lift configuration create unsteady flow structures which inherently generate noise. For devices such as flaps, spoilers and the undercarriage there is a strong correlation between overall noise and drag such that, in the quest for quieter aircraft, one challenge is to generate drag at low noise levels. This paper presents a rigorous aero-acoustic assessment of a novel drag concept. The idea is that a swirling exhaust flow can yield a steady, and thus relatively quiet, streamwise vortex which is supported by a radial pressure gradient responsible for pressure drag.

show abstract

mentioning

confidence: 99%

Aeroacoustics of Drag-Generating Swirling Exhaust Flows

Shah¹,

Mobed²,

Spakovszky³

et al. 2010

AIAA Journal

View full text Add to dashboard Cite

show abstract

A Novel Turbomachinery Air-Brake Concept for Quiet Aircraft

Shah

Mobed

Spakovszky

2010

Journal of Turbomachinery

View full text Add to dashboard Cite

A novel air-brake concept for next-generation, low-noise civil aircraft is introduced. Deployment of such devices in clean airframe configuration can potentially reduce aircraft source noise and noise propagation to the ground. The generation of swirling outflow from a duct, such as an aircraft engine, is demonstrated to have high drag and low noise. The simplest configuration is a ram pressure-driven duct with stationary swirl vanes, a so-called swirl tube. A detailed aerodynamic design is performed using first principles based modeling and high-fidelity numerical simulations. The swirl-drag-noise relationship is quantified through scale-model aerodynamic and aeroacoustic wind tunnel tests. The maximum measured stable flow drag coefficient is 0.83 at exit swirl angles close to 50 deg. The acoustic signature, extrapolated to full-scale, is found to be well below the background noise of a well-populated area. Vortex breakdown is found to be the aerodynamically and acoustically limiting phenomenon, generating a white-noise signature that is about 15 dB louder than a stable swirling flow.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Swirling-flow jet noise suppressors for aircraft engines

Cited by 2 publications

References 3 publications

Aeroacoustics of Drag-Generating Swirling Exhaust Flows

Aeroacoustics of Drag-Generating Swirling Exhaust Flows

A Novel Turbomachinery Air-Brake Concept for Quiet Aircraft

Contact Info

Product

Resources

About