Retroreflective shadowgraph of clustered rocket nozzles

Cánchero, Andrés

Retroreflective shadowgraph of clustered rocket nozzles

dc.contributor.advisor	Tinney, Charles Edmund, 1975-	en
dc.contributor.committeeMember	Clemens, Noel T.	en
dc.creator	Cánchero, Andrés	en
dc.creator.orcid	0000-0003-0971-7537	en
dc.date.accessioned	2015-10-13T18:30:04Z	en
dc.date.available	2015-10-13T18:30:04Z	en
dc.date.issued	2015-05	en
dc.date.submitted	May 2015	en
dc.date.updated	2015-10-13T18:30:04Z	en
dc.description	text	en
dc.description.abstract	The plume produced by a cluster of two large area-ratio thrust optimized parabolic contour nozzles is visualized over a range of nozzle pressure ratios by way of retroreflective shadowgraphy. Both nozzles exhibit free shock separated flow, restricted shock separated flow and an end-effects-regime prior to flowing full. Experimental tests were conducted in the anechoic chamber and high speed flow facility at The University of Texas at Austin. Steady and transient (start-up) operations of the nozzles are studied with the primary focus being the end effects regime. This occurs at a pressure ratio of 37 for these nozzles and is associated with elevated sound levels in the immediate vicinity of the nozzles and vehicle. The shadowgraphy images reveal the formation of turbulent large scale structures, on the order of the nozzle diameter, during the end effects regime. These large scale structures are driven by the intermittent opening of the last trapped annular separation bubble with the ambient which grow rapidly within the first two nozzle diameters. Radon transforms of the spatially resolved shadowgraphy images are then used to characterize the statistical behavior of the acoustic wavefronts that reside within the hydrodynamic periphery of the nozzle flow during fixed operations of the nozzle cluster. Acoustic loads are assessed by synchronizing an eighth-inch microphone with the shadowgraphy images. The findings reveal basic principles to understand the sources of most intense vibro-acoustic loads during the end effects regime.	en
dc.description.department	Aerospace Engineering	en
dc.format.mimetype	application/pdf	en
dc.identifier	doi:10.15781/T2J88T	en
dc.identifier.uri	http://hdl.handle.net/2152/31712	en
dc.language.iso	en	en
dc.subject	Retroreflective shadowgraphy	en
dc.subject	End-effects-regime	en
dc.subject	Rocket propulsion	en
dc.subject	Aeroacustics	en
dc.subject	Time frequency analysis	en
dc.title	Retroreflective shadowgraph of clustered rocket nozzles	en
dc.type	Thesis	en
thesis.degree.department	Aerospace Engineering	en
thesis.degree.discipline	Aerospace Engineering	en
thesis.degree.grantor	The University of Texas at Austin	en
thesis.degree.level	Masters	en
thesis.degree.name	Master of Science in Engineering	en