Boundary-value solutions of the one-dimensional laminar flame propagation equations

✍ Scribed by Kenneth A. Wilde

• Publisher: Elsevier Science
• Year: 1972
• Tongue: English
• Weight: 704 KB
• Volume: 18
• Category: Article
• ISSN: 0010-2180
• DOI: 10.1016/0010-2180(72)90031-4

✦ Synopsis

The classic flame problem has been treated as a boundary-value problem using powerful new techniques for difficult multi-variable equa'.ions. Efficient solution methods and general computer programs for arbitrary chemical species ant' reactions have b~en developed. Although .,~ap,~ed transport equations were used, the approach is readily extended to any level of complexity just/fled by the transport and kineti: d-_ta available. Th~e flame systems have been studied initially: 03-02, H2-Br2, and H=-O 2. Solutions have been obtained for the ozone decomposition flame at concentrations including 100% O 3. The calculated values of the flame velocity were about twize the experimental ones, in contrast to previous good agreement in early computations by othci workers.

The solution techniques are now v:ell established so that the kinetic and transport data ~ well as the basis of the comparison with the exp.~imental data must be suspect. Results on the H 2 -Br= flame indiczte that the steady-state approximation in flames is largely inappfi~ble, and in any case, is of tittle help in a general approach. Solution prof'des for Ha-O= indicate that HO 2 and H~O= are kinetically important species under many conditions in H 2-O 2 flames. In all the ~bo_ve flames, reasonable solutions have been found with a single parameter (eigenvalue), the flame velocity. The techniques which have been developed should make feasible inter-relations of overall flame structure data and elementary kinetic steps heretofore impossible. The feas~ility of complex multi-reaction kinetics in more compficated flow situa,.ions involving boundary value problems, such as bcundary layers and imperfectly stirred reactors, is ~so indicated by the present work.