Kim, J.S. Gubernov, V.V. 2024-01-12T08:16:47Z 2024-01-12T08:16:47Z 2022-03-07 2005-07 0000-0000 https://pubs.kist.re.kr/handle/201004/82021 Fast-time instability is investigated for diffusion flames with Lewis numbers greater than unity by employing the numerical technique called the Evans function method. Since the time and length scales are those of the inner reactive-diffusive layer, the problem is equivalent to the instability problem for the Li？？n's diffusion flame regime. The instability is primarily oscillatory, as seen from complex solution branches and can emerge prior to reaching the upper turning point of the S-curve, known as the Li？？n's extinction condition. Depending on the Lewis number, the instability characteristics is found to be somewhat different. Below the critical Lewis number, Lc, the instability possesses primarily a pulsating nature in that the two real solution branches, existing for small wave numbers, merges at a finite wave number, at which a pair of complex conjugate solution branches bifurcate. For Lewis numbers greater than Lc, the solution branch for small reactant leakage is found to be purely complex with the maximum growth rate found at a finite wave number, thereby exhibiting a traveling nature. As the reactant leakage parameter is further increased, the instability characteristics turns into a pulsating type, similar to that for L < L c. English On oscillatory fast-time instability of diffusion flames Conference 1 5th Asia-Pacific Conference on Combustion, ASPACC 2005, pp.377 - 380 5th Asia-Pacific Conference on Combustion, ASPACC 2005 377 380 AT Adelaide, SA 2005-07-17 5th Asia-Pacific Conference on Combustion, ASPACC 2005: Celebrating Prof. Bob Bilger's 70th Birthday 2-s2.0-84878993300