Periodic mixing and combustion processes in gas fired pulsating combustors
✍ Scribed by D. Reuter; B.R. Daniel; J. Jagoda; B.T. Zinn
- Publisher
- Elsevier Science
- Year
- 1986
- Tongue
- English
- Weight
- 595 KB
- Volume
- 65
- Category
- Article
- ISSN
- 0010-2180
No coin nor oath required. For personal study only.
✦ Synopsis
Although gas fired pulse combustors for home and water heating have been in use for a number of years, little research has been carried out, to date, to develop an understanding of the fundamental physical and chemical processes which control the operation of the pulse combustors. Consequently, the past developments of such combustors have been based upon costly trial-and-error approaches. This paper describes some results of an ongoing investigation which studies controlling processes in valved pulse combustors. Specifically, this paper provides experimental data which describe the mixing of the reactants, the time dependence of the combustion process heat release rate, its phase relationship with the combustor pressure, and the spatial characteristics of the combustion process. High speed shadow and Schlieren photography was carried out on a partially transparent pulse combustor. The combustion was observed to take place largely in the mixing chamber. Fuel and air jets enter the mixing chamber prior to the combustor reaching its minimum pressure. The two jets impinge, and mix and the new reactants are ignited by entrained remnants of reacting pockets from the previous cycle. This ignition takes place at the location and time at which the two reactant streams first mix. The resultant reactive stream breaks into two opposing vortices which fill the mixing chamber. Finally, data from C-H and C-C radiation measurements showed that the reaction is periodic and that it remains nonzero throughout the entire cycle. Furthermore, the reaction rate is in phase with the combustion pressure oscillations, satisfying Rayleigh's criterion for wave driving by heat addition. * This work is supported by the Gas Research Institute under valves. The gases mix and combustion is initiated Grant No. 5083-260-0873. Mr. J. Kezerle is the monitor, using a spark plug. As the combustion proceeds,