Original title: Jet flow issuing from an axisymmetric pipe-cavity-orifice nozzle
Authors: Broučková, Zuzana ; Pušková, P. ; Trávníček, Zdeněk ; Šafařík, P.
Document type: Papers
Conference/Event: Experimental Fluid Mechanics 2015 /10./, Praha (CZ), 2015-11-17 / 2015-11-20
Year: 2015
Language: eng
Abstract: Axisymmetric air jet flow is experimentally investigated under passive flow control. Jet issues from a pipe (inner diameter 10mm, length 150 mm) equipped with an axisymmetric cavity at the end. Cavity operates as resonator creating self-sustained acoustic excitations. Mechanism of excitations is complex. Experimental methods were: flow visualization, microphone measurements and velocity measurements by the Pitot probe. Power spectral density (PSD) and sound pressure level (SPL) were evaluated from microphone measurements. Jet Reynolds number ranged Re = 1600–18 000. Peaks in PSD indicated a function of the resonator. The most effective acoustic response was found at higher Re. Results demonstrate effects of the control: mixing and velocity decay along the axis are intensified. It causes shortening of the transition region. However, an inverse proportionality of the velocity decay in the fully developed region is not changed. Momentum and kinetic energy fluxes decrease more intensively.
Keywords: acoustic excitations; passive control; resonator
Project no.: GA14-08888S (CEP)
Funding provider: GA ČR
Host item entry: Experimental Fluid Mechanics 2015

Institution: Institute of Thermomechanics AS ČR (web)
Document availability information: Fulltext is available at the institute of the Academy of Sciences.
Original record: http://hdl.handle.net/11104/0254909

Permalink: http://www.nusl.cz/ntk/nusl-201371


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Research > Institutes ASCR > Institute of Thermomechanics
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