摘要:

A simplified analysis of monopropellant spray combustion was developed, based on the locally-homogeneous-flow approximation of multiphase flow theory and the thin-flame approximation of turbulent premixed flame theory. The performance of the analysis was evaluated using shadowgraphs of spray flames for a hydroxyl ammonium nitrate (HAN)-hased liquid monopropellant at ambient pressures of 6-8 MPa. Predictions showed that these spray flames are very sensitive to the degree of flow development at the injector exit, with fully-developed turbulent flows requiring significantly smaller combustion volumes than slug flows having low initial turhulence levels. There was encouraging agreement between predictions and measurements; however, uncertainties concerning injector exit conditions for the experiments precluded definitive assessment of the analysis

ISSN:0010-2202    

DOI:10.1080/00102208808923946

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

ISSN:0010-2202    

DOI:10.1080/00102208808923947

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The purpose of this paper is to present an asymptotic analysis of the laminar mixing of and the simultaneous chemical reaction between parallel supersonic streams of two reacting species. The study is based on a one-step irreversible Arrhenius reaction and on large activation energy asymptotics. Esssenlially it extends the work of Linan and Crespo to include the effect of free shear and Mach number on the ignition regime, the deflagration regime and the diffusion flame regime. It is found that the effective parameter is the product of the characteristic Mach number and a shear parameter.

ISSN:0010-2202    

DOI:10.1080/00102208808923948

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

The probability density functions of a passive scalar quantity are calculted in a perturbed mixing layer by means of direct numerical simulations. The results indicate that the two-dimensional rolkip of the unsteady shear layer, and the pairing process in particular, contributes greatly to the generation of the predominant peak of the PDFs within the mixing region,

ISSN:0010-2202    

DOI:10.1080/00102208808923949

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

A simple spark ignition engine cycle model has been used to illustrate the concept that cycle-to-cycle variations are an inherent consequence of non-linear combustion kinetics. Sample calculations show highly chaotic behavior when the burn time occupies an excessive fraction of the cycle time. The results are consistent with the well known fact that the engine designer must strive to shorten the burn time as much as possible to minimize variations.

ISSN:0010-2202    

DOI:10.1080/00102208808923950

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor

摘要:

Spatial and temporal profiles of soot particle diameters were obtained in premixed, flat, ethylene-oxygen-argon flames stabilized with either a flat plate or a chimney. Vertical components of the gas flow velocities were determined by a soot vaporization technique which was demonstrated to be accurate for velocity measurements in these flames. Although a difference in the rate of growth and final diameters of particles in the plate- and chimney-stabilized flames would be inferred from the spatial profiles, the temporal profiles indicate no difference in particle growth or size.

ISSN:0010-2202    

DOI:10.1080/00102208808923951

出版商:Taylor & Francis Group    

年代:1988

数据来源: Taylor