A numerical analysis of flame flashback in a premixed laminar system

✍ Scribed by S.T. Lee; J.S. T'ien

• Publisher: Elsevier Science
• Year: 1982
• Tongue: English
• Weight: 699 KB
• Volume: 48
• Category: Article
• ISSN: 0010-2180
• DOI: 10.1016/0010-2180(82)90134-1

✦ Synopsis

The flashback and the structure of premixed laniinar flames are investigated theoretically. The mathematical model includes the axisymmetric Navier-Stokes energy and species equations with one-step overall chemical reaction and second-order finite rate Arrhenius kinetics. Flashback is examined as a function of incoming velocity profiles, wall velocity gradients, and tube radius. Flame structure at the flashback limit indicates the intrinsic multidimensional nature of the flashback phenomena. The flame is found to generate a local pressure plateau near the flame front which causes an upstream influence on the incoming flow. The calculated flame velocity is shown to be greater than the one-dimensional premixed flame speed, and this is attributed to the flame-pressure interaction. The limitation of using the quasi-onedimensional velocity balance concept as a predicting tool for flashback is discussed.