Tsuji type counter flow burner
Non-premixed flame established in the boundary layer of oxidizer flow past a porous cyclinder issuing fuel is commonly used for characterizing extinction. This configuration is known as the Tsuji burner. It was used extensively by Tsuji and co-workers from 1960 till 1980 to study extinction of non-premixed flames. Opposed jet configuration became the preferred choice after this point and extensive studies have been performed over the last four decades covering a wide range of fuel-oxidizer combinations. The principal reason for this transition is likely to be the dependence of measured extinction strain rate values on the diameter of the porous cylinder; that the flow is not strictly 1D in Tsuji type burner leading to flame curvature effects at smaller diameters and associated 2D effects on the measured extinction strain rates are the possible causes for this. Unlike this, the flames in opposed jet configuration are flat. But even here, the measured extinction strain rate is a function of nozzle separation distance. Preliminary 2D CFD simulations for opposed jet configuration have shown that there exist a nozzle separation distance L* where the extinction occurs at the same value of a_g for 1D and 2D computations. Therefore, experimental determination of a_g for validation of kinetic mechanisms using 1D framework requires a prior estimate of L* and hence inputs from 2D CFD and experimental results for the range of L. In the light of this, there is a possibility of using the much simpler Tsuji configuration for experimentally determining a_g, which can later be used for optimization of kinetic mechanisms using a combination of 1D and 2D numerical simulations. With this principal aim, a Tsuji burner has been developed in our lab; it is designed to accomodate different burner diameters ranging from 5 to 50 mm and is currently being used to study extinction characteristics of different gaseous fuels and its geometric dependence.
Tsuji type counter flow burner
Faculty incharge:
Dr. S. Varunkumar