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Thermoacoustic instability which stems from the non-linear interactions between heat release and pressure waves in a confined combustion chamber, can create large amplitude pressure oscillations. These oscillations may cause significant damage to the combustor hardware, and even surroundings. Accurate characterization and prediction of such instability is challenging due to its inherent complexities arising from the non-linear nature of the problem.In this thesis, we design a Rijke tube, a device in which self-excited thermoacoustic instabilities can be studied for relatively simple flame geometries. Subsequently, we used the Rijke tube to investigate dynamics of thermoacoustic instability in premixed laminar flame. We focused on the role of burner design on the ensuing instability and flame dynamics by investigating pressure oscillations observed in four different single- and multi-flame burners. We observed that %a single- and seven-flame burner tip using similar flame conditions were experimentally compared, by recording pressure data. The the single-flame burner did not display transition to an unstable state, when the burner was traversed along the length of the Rijke tube, while a seven-flame burner showed various states of instability and multiple bifurcation points. This observation confirms that the increased degree of freedom, arising from the interaction between individual flames in a multi-fame burner, is responsible for the wider dynamics observed.Subsequently, to quantify the dynamics of individual flames and their roles in the ensuing pressure dynamics, a three flame burner, where the flames are located in-line, were studied in details. The Phase Lock Value, Root Mean Frequency, and Power Spectral Density were analyzed for the heat release rates from individual flames and the acoustic pressure. We observed that the center flame possessed stronger synchronization with the pressure. But, the left and right flames shared a few modes (frequencies) of osci

Should we stop teaching critical thinking? Meant as a prompt to further discussion, Critical Condition questions the assumption that every student should be turned into a “critical thinker.” The book starts with the pre-Socratics and the impact that Socrates’ death had on his student Plato and traces the increasingly violent use of critical “attack” on a perceived opponent. From the Roman militarization of debate to the medieval Church’s use of defence as a means of forcing confession and submission, the early phases of critical thinking were bound up in a type of attack that Finn suggests does not best serve intellectual inquiry. Recent developments have seen critical thinking become an ideology rather than a critical practice, with levels of debate devolving to the point where most debate becomes ad hominem. Far from arguing that we abandon critical inquiry, the author suggests that we emphasize a more open, loving system of engagement that is not only less inherently violent but also more robust when dealing with vastly more complex networks of information. This book challenges long-held beliefs about the benefits of critical thinking, which is shown to be far too linear to deal with the twenty-first century world. Critical Condition is a call to action unlike any other.