Experimental Investigations of Screech Mitigation and Amplification by Beveled and Double-Beveled Nozzles Show others and affiliations
2022 (English) In: Journal of Aerospace Engineering, ISSN 0893-1321, E-ISSN 1943-5525, Vol. 35, no 4, article id 04022050Article in journal (Refereed) Published
Abstract [en]
An experimental study was conducted to investigate and compare the effects of beveled and double-beveled circular nozzles on supersonic jet screech at a nozzle pressure ratio of 5. In particular, near- and far-field microphone measurements and schlieren visualizations were utilized to look into selected acoustic and flow features associated with jet screech radiation. Results show that beveled nozzles eliminate jet screech by producing asymmetric shock structures and instability waves that are mismatched in phase and amplitude. In contrast, double-beveled nozzles produce symmetric shock structures and amplify screech intensity, even when jet mixing effects have been significantly enhanced. It is further observed that amplified jet screeches produced by double-beveled nozzles are highly unsteady and undergo nonperiodic and stochastic temporal variations. Last but not least, double-beveled nozzles also significantly impact screech peak noise locations and confer different changes along different measurement planes. The present study demonstrates that not all beveled-type nozzles are able to mitigate jet screech, with nonoptimal designs amplifying it instead.
Place, publisher, year, edition, pages American Society of Civil Engineers (ASCE) , 2022. Vol. 35, no 4, article id 04022050
Keywords [en]
Supersonic jet noise, Shock noise, Screech, Acoustic measurements, Lip-modified nozzle
National Category
Fluid Mechanics
Identifiers URN: urn:nbn:se:kth:diva-313305 DOI: 10.1061/(ASCE)AS.1943-5525.0001447 ISI: 000796078600025 Scopus ID: 2-s2.0-85129263367 OAI: oai:DiVA.org:kth-313305 DiVA, id: diva2:1663586
Note QC 20220602
2022-06-022022-06-022025-02-09 Bibliographically approved