Humankind has fascinated itself with technology ever since the discovery of fire. It is the hunger to know more that leads to research for things. But, the boon of technology comes with a cost of living and enduring it for generations. One such radical change, that transformed our imagination of flying into reality is the invention of air-crafts. Rapid growth of aviation industry after the world war was the achievement of this long-lived dream of humankind. Even though the graph of development was rising but so were its adverse effects on the nature and life. Release of soot and non-volatile particulate matter(nvPM) into atmosphere is one of the problems that started affecting health and well-being of life on earth and since then the measures to counter this problem are under constant monitoring and study. Present work intends to provide a comprehensive understanding of the soot formation in swirl stabilized gas turbine turbulent flames in high pressure environments up to 10bar. Non-intrusive optical diagnostics is employed to study the course of soot through different zones of RQL combustor.

Conventional techniques of laser diagnostics including Laser Induced Incandescence (LII), Planar Laser Induced Fluorescence (PLIF) etc. were being in practice for over a decade now and has known to deliver fruitful results. However, some limitations were noted. Current study employs a novel LII technique to study soot volume fraction and mean particle size distribution inside an optical RQL combustor. Additionally, PLIF of OH and CH is also planned to obtain the temperature distribution and flame location respectively. Results of this research are expected to aid in developing state-of-art soot prediction model.