Thermoacoustics

Thermoacoustic instabilities

Thermoacoustic systems contain multiphysics and encompass multiple scales. Thermoacoustic instabilities occur whenever there is a positive feedback between a source of unsteady heat release and the enclosing acoustic fi eld. Being large amplitude self-sustaining oscillations, thermoacoustic instabilities can easily cause the rocket engines, gas turbines or combustor to vibrate excessively or to even fail. During such instabilities, thermoacoustic systems display a wide variety of asymptotic dynamical behaviour; from steady states to chaotic trajectories. The ability to control the nature and characteristics of thermoacoustic oscillations is therefore a desired capability.

Collaborators:

 – Raman I. Sujith             

 – Sathesh Mariappan                           

 – Ralf Blumenthal

 – Pankaj Wahi                                           

 – Niket Kaisare                                     

 Pushkarini Agharkar     

 – Wolfgang Polifke

Relevant Publications:

6. Distributed Time Lag Response Functions for the modelling of Combustion Dynamics, Combustion Theory & Modelling, 19(2), 223-237, 2015.

5. Thermoacoustic instabilities in a ducted premixed flame: reduced order models & control, Combustion Science & Technology, 185(6), 920-942, 2013.

4. Novel Perspectives on the Dynamics of Premixed Flames, Combustion & Flame, 160, 1215-1224, 2013.

3. Subcritical bifurcation and bistability in thermoacoustic systems, Journal of Fluid Mechanics, 715, 210-238, 2013.

2. Non-normality & internal flame dynamics in premixed flame-acoustic interaction, Journal of Fluid Mechanics, 679, 315-342, 2011.

1. Bifurcation analysis of thermoacoustic instability in a Rijke tube, International Journal of Spray & Combustion Dynamics, 2(4), 325-356, 2010.