DIFFUSION FLAMES AND SUPERSONIC COMBUSTION.
Abstract
Some problems related to the fluid dynamical and chemical phenomena appearing near the injector exit of an idealized supersonic combustion burner, are theoretically investigated. The ignition delay length is calculated under the assumption that fuel(hydrogen) and oxidizer (air) mix without appreciable concentration change and heat release resulting from chemical reactions, although radicals, mainly atomic hydrogen, are produced. The chemical kinetics scheme is reduced to one overall chemical reaction. The presence of radicals introduced in the mixing zone from outside is taken into account. The fluid dynamic pattern corresponds to a two-dimensional constant pressure shear layer. It is shown that dissociation at the injector outer boundary layer controls in many cases the ignition delay length. Since when hydrogen is injected into a coflowing supersonic stream of air, a wake-like recirculating configuration appears, the ignition delay lengths were compared with some experimental data on near wake lengths, to show that, in most cases of interest, recirculation would enhance the ignition mechanism. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1967
- Accession Number
- AD0663741
Entities
People
- A. Linan
- E. Fraga
- I. Da-riva
- J. L. Urrutia