Abstract: Various kinds of oscillatory instabilities are seen in practical systems. We devise of way of combating these oscillatory instabilities in a thermoacoustic system. Confined combustion environments are prone to large amplitude pressure oscillations known as thermoacoustic instabilities. Although several techniques have been employed to control or mitigate such instabilities, optimization of these methods is achieved at the cost of performing multiple trial and error experiments/simulations. This invention develops a methodology to quantify the spatio-temporal dynamics using synchronization, recurrence, and fractal measures and find the coherent region in such turbulent flow field. Such an analysis provides us with a novel way to detect critical regions responsible for thermoacoustic instability, and other oscillatory instabilities in general, in the flow field and implement an optimized control strategy at these regions.

Abstract: A system and method for optimizing passive control strategies of oscillatory instabilities in turbulent systems using finite-time Lyapunov exponents are disclosed. The method includes receiving data from one or more measuring devices connected to the turbulent flow system incorporating a control strategy in the flow field. One or more flow characteristics are determined from the data obtained from the measuring devices. The method involves computing critical dynamics from backward time finite-time Lyapunov exponent (FTLE) field based on the one or more flow characteristics. Next, one or more regions of critical dynamics associated with impending oscillatory instabilities in the turbulent flow system are identified. The identified region of critical dynamics is disrupted the control the onset of oscillatory instabilities in the turbulent flow system.

Abstract: Various kinds of oscillatory instabilities are seen in practical systems. We devise of way of combating these oscillatory instabilities in a thermoacoustic system. Confined combustion environments are prone to large amplitude pressure oscillations known as thermoacoustic instabilities. Although several techniques have been employed to control or mitigate such instabilities, optimization of these methods is achieved at the cost of performing multiple trial and error experiments/simulations. This invention develops a methodology to quantify the spatio-temporal dynamics using synchronization, recurrence, and fractal measures and find the coherent region in such turbulent flow field. Such an analysis provides us with a novel way to detect critical regions responsible for thermoacoustic instability, and other oscillatory instabilities in general, in the flow field and implement an optimized control strategy at these regions.

Abstract: A system and method for optimizing passive control strategies of oscillatory instabilities in turbulent systems using finite-time Lyapunov exponents are disclosed. The method includes receiving data from one or more measuring devices connected to the turbulent flow system incorporating a control strategy in the flow field. One or more flow characteristics are determined from the data obtained from the measuring devices. The method involves computing critical dynamics from backward time finite-time Lyapunov exponent (FTLE) field based on the one or more flow characteristics. Next, one or more regions of critical dynamics associated with impending oscillatory instabilities in the turbulent flow system are identified. The identified region of critical dynamics is disrupted the control the onset of oscillatory instabilities in the turbulent flow system.