Research Center for Engineering of
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Title: Numerical Assessment of a Novel Concept for Mitigating the Unsteady Pressure Pulsations Associated to Decelerating Swirling Flow with Precessing Helical Vortex
Published In: International Conference of Computational Methods in Sciences and Engineering, AIP Conference Proceedings, vol. 1702, Athens, Greece
Description: Decelerated swirling flows in conical diffusers can develop self-induced instabilities for some configurations of incoming flow. As a result, an upstream steady and axis-symmetrical flow becomes unsteady and three-dimensional with associated pressure fluctuations that hinder the operation of tubomachines. This paper introduces a new approach for mitigating the swirling flow instabilities using a diaphragm into the cone. As a result, the severe flow deceleration is diminished, taming the precessing helical vortex and its associated pressure fluctuations. A full three-dimensional unsteady numerical study is performed for swirling flow apparatus developed at the Politehnica University of Timisoara. Fourier spectra corresponding to unsteady numerical data acquired without and with diaphragm are compared in several locations displaced along to the element of the cone in order to assess the novel concept. It is clearly revealed that the diaphragm mitigates the unsteadiness effects associated to the swirling flow with precessing helical vortex in the conical diffuser. The novel concept paves the way towards a new passive control technique.
Publication year: 2015
Keywords:numerical assessment, new concept, precessing helical vortex, conical diffuser
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Authors: TANASA Constantin , SUSAN-RESIGA Romeo , MUNTEAN Sebastian , STUPARU Adrian , BOSIOC Ilie Alin , CIOCAN Tiberiu ,
Type: International Conference Proceedings
Laboratory: Numerical Simulation and Parallel Computing Laboratory
Institution: UPT