Thermoacoustics


Half of my research work belongs to another area of Fluid Mechanics, namely Thermoacoustics. The subject of this science is the heat-sound interactions. Combustion instability in rocket motors, biomedical thermoacoustic tomography, and thermoacoustic refrigerators are just a few examples of applications of this science. I did my Ph.D. (at Caltech) and my post-doc (at Los Alamos National Lab) working primarily on thermoacoustic instability and nonlinear thermoacoustic effects. Some of my projects are illustrated below. They include:
Rijke tube (at Caltech)
Acoustically forced combustor (at Caltech)
Acoustic-vortex-combustion instability (at Caltech and Los Alamos)
Thermal end effect in pulse tubes (at Los Alamos)
Gravity effect on streaming (at Los Alamos)

More detailed information about these projects and results of research projects can be found my Acoustics papers.

My PhD thesis was on thermoacoustic instabilities in a Rijke tube. This device effetively simulates combustion (thermoacoustic) instability occuring in rocket and airplane engines and industrial burners. Below shown is the experimental system and some results on the transition to instability, exhibiting hysteresis at high flow rates.





I also participated in the study of the acousticall excited combustor using a laser diagnostic system.
Experimental system:


I developed and validated a model for combustion instability coupled with vortex-acoustic phenomena in chambers with sudden expansions.
Process schematics:


I built an experimental high-pressure system for studying nonlinear thermoacoustic phenomena related to pulse tubes and thermoacoustic engines.
Experimental system:


I also developed a model to account for the gracity influence on acoustic streaming, which is a common phenomenon in thermoacoustic systems.
Thermal buffer tube:


For more information on the cutting-edge thermoacoustic research, please refer to Los Alamos Thermoacoustics.