Experimental Studies on Laminar Jet Methane-Air Premixed Flame at Atmospheric Condition

International Journal of Research and Scientific Innovation (IJRSI) | Volume VII, Issue VIII, August 2020 | ISSN 2321–2705

Experimental Studies on Laminar Jet Methane-Air Premixed Flame at Atmospheric Condition

Jahidul Haque Chaudhuri
Direct Ph.D., Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai, 600036, India

Abstract: Flame can be defined in which rapid chemical reaction take place and often emitting light. In other words, flame is a self-sustainable localized combustion zone that moves at a certain velocity into the fuel-air mixture. This is also known as a combustion wave since it moves and there is a sudden change in properties like temperature and mass fraction of constituent species. Combustion can occur in both in flame and non-flame method. Flame mode further classified premixed flame and non-premixed fame. A premixed flame can be stabilized between two limiting values of gas flow rate. First limiting value of gas flow rate is, for a certain maximum value of gas flow rate flame get detached from the burner and flame go away from the domain of interest. This phenomenon is called blow off or liftoff the flame. During liftoff condition flame may be stabilized at some distance from the port. Due to liftoff, several problems create like escape or loss of unburnt gasses, poor heat transfer, noisy, incomplete combustion, and tough to accurately control the position of flame. And second, the limiting value of gas flow rate is, when the flow rate of the gas falls below a certain minimum value, the flame is not capable of anchoring itself to the burner rim and moves into the burner, this phenomenon is called flashback. Similar to liftoff conditions due to flashbacks create several problems as it can lead to an explosion. So data off flashback and blow off is very important to design any combustion system. In this present study focusing on finding stability range of methane-air experimentally by investigating flashback and blow off covering a wide range of fuel-air ratio from lean to reach mixture. And also observe how cone angle and flame height changes with changing air-fuel flow rate, using flame cone angle flame propagation speed can measure and compare at which condition (lean, rich, stoichiometric) its maximum.

Keywords- Methane-air mixer, Stability-limit, Premixed-flame, laminar, lean, Rich, Stoichiometric.

I. INTRODUCTION

Laminar flame speed is one of the important parameter of the flame, it’s used in various area like as a basic data to examine the flame instability or as a validation data to refine chemical kinetics model. The study of earlier works reveals that a great deal of work has been carried out in areas of stability of premixed hydrocarbon flame. Stability of propane air flames determined by flashback and blow off investigated by chen and Churchill [1]. Mishra [2] experimentally investigated the stability range of CNC-air premixed flame. He also observed that the flashback limit could be enhanced with an increase in burner diameter.

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