EXPERIMENTAL AND THEORETICAL INVESTIGATION OF ACOUSTIC INSTABILITY IN PREMIXED FLAMES OF FUEL-BLENDS

Abstract

A major problem in many combustion systems, such as gas turbines, industrial furnaces, and propulsion systems, is acoustic instability. This phenomenon can result in harmful outcomes like flame extinction, pressure oscillations, and structural damage. It is characterized by the coupling between acoustic oscillations and combustion processes. This research aims to comprehensively investigate acoustic instability in premixed flames through experimental analysis and numerical simulations for fuel-blends. The paper begins with an introduction under which basic introduction of Markstein number, counterflow flame and acoustic instability has been discussed. It then discusses the fundamentals related to acoustic instability as: combustion, thermochemistry, thermodynamics and criterion related to that. The paper also covers the effects of acoustic instability on flame dynamics, Characteristics of acoustic instability. The literature review and research gap are also added to overcome the previous problems. The methodology used to determine the Markstein number, which aids in drawing the instability curve, has been discussed. Following this, the experimental procedure has been described. Subsequently, results for various fuels have been included which showing the variation of Markstein number with equivalence ratio and instability curve has been shown. Finally, the paper concludes with a summary of the research and references used throughout the report.