Modeling coherent wavepackets in jets issuing from serrated nozzles

We have developed models based on linear parabolized stability equation (PSE) theory for the coherent wavepackets in jets issuing from serrated nozzles (also called chevron jets). Subsequently, we have used this modelling technique to understand the effect of varying the chevron geometry on the stability characteristics of such jets, in an effort to predict the corresponding noise behaviour. The overall aim is to optimally design the chevron geometry for noise mitigation, with minimal computational effort.

Selected publications:

  • A. Sinha, A. Rajagopalan and S. Singla, Linear stability implications of chevron geometry modifications for turbulent jets, AIAA Paper 2016-3053 (download)
  • A. Sinha, K. Gudmundsson, H. Xia and T. Colonius, Parabolized stability analysis of jets from serrated nozzles, Journal of Fluid Mechanics, 789:36-63, 2016 (download)
  • A. Sinha and T. Colonius, Linear stability implications of mean flow variations in turbulent jets issuing from serrated nozzles, AIAA Paper 2015-3125 (download)

Modeling coherent wavepackets in dual-stream jets

The parabolized stability equation (PSE) theory is applied to dual-stream coaxial jets in an effort to predict the coherent wavepackets existing therein. In collaboration with Prof. Datta V. Gaitonde of Ohio State University (Columbus, Ohio, USA), we have compared the model results against Large-Eddy Simulation (LES) data of two such coaxial jets, with reasonable success. The ultimate goal is to add to the toolkit for prediction of noise reduction potential of offset multi-stream jets that are being experimentally evaluated at present.

Selected publications:

  • A. Sinha, D. V. Gaitonde and N. Sohoni, Parabolized stability analysis of dual-stream jets, AIAA Paper 2016-3057 (download)