Short Description:
We investigate flow asymetry and self-sustained oscilalations in cavities with confined jet under geometricaly symetric conditions. Numerical method provide observations of long-term behaviour of the confined jet.  Simulations in "original chamber" were performed according to experiments reported in the article of A Maurel, P Ern, B J A Zielinska and J E Wesfreid: "Experimental study of self-sustained oscillations in a confined jet", Phys Rev. E, 54, 3643-3651, 1996. Their results were well reproduced and, morover, aditional features like oscillating jet periodical drift has been  found. Additional simullations were performed in "modified chamber" and jet drift and oscillations has been further studied under variable chamber length, size grid density, grid perturbations and initial conditions perturbations.  Chaotic-like behaviour has been observed the sources of which are currently investigated.

Original chamber

Modified chamber

 

Image gallery: click on a picture to enlarge!

Project type: Basic research

The aim of research: Identifying physical and numerical sources of instabilities and chaotic-like behaviour

Implementation: Beter understanding of numerical method reliability  in various applications.

Tools: EDS-SDRC IDEAS, ICCM Comet

Authors: Joze Duhovnik, Nikola Jelic, Tomaz Kolsek

Additional documents:
- 3D streakline animation (mpeg 20.5MB)