摘要:

—The non-similar weakly-reactive boundary layer flow over an isothermal flat plate is studied using a combined perturbation/numerical procedure. The solution yields an explicit ignition criterion which exhibits the proper functional dependence on all the system parameters of interest. Predictions on the minimum distance to achieve ignition agree well with results from complete numerical calculations. Reactant consumption is shown to be an important factor, especially for lean mixtures. Its inclusion enables the identification of an approximate expression for the absolute ignition limit of the system.

ISSN:0010-2202    

DOI:10.1080/00102208108547516

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

—The unsteady one-dimensional cyclic absorption and desorption of a dilute amount of gas in a thin (constant-thickness),isothermal (constant-property) liquid layer on an impervious noncatalytic wall is examined. The pertinent conditions are taken to be (1) thermodynamic equilibrium (such that Henry's law holds at the two-phase interface), and (2) diffusional resistance of the liquid layer being rate-controlling (such that the problems for the liquid layer, and for the bulk gas contiguous to it, decouple). Specifically, the mass fraction of the gaseous species of interest is taken to be known, and of square-wave periodic character, at the two-phase interface, so attention is concentrated on the total gaseous content of the liquid layer as a function of time. While start-up (in which the liquid layer is taken to be initially free of gaseous content) is considered, primary interest is in steady periodic operation in which no residual influence of the initial condition remains. The model is developed as one step in a series of simplistic characterizations of hydrocarbon absorption/desorption in the motor oil coating side walls in reciprocating-piston-type internal-combustion-engine cylinders, of concern as a possible prime source of undesirable unburned-hydrocarbon emissions in the cylinder exhaust. The role of spark timing and of engine speed on the phenomena is given focus, and, in particular, the experimentally observed decrease of unburned-hydrocarbon content with increasing rpm is consistent with the model.

ISSN:0010-2202    

DOI:10.1080/00102208108547517

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

—In order to investigate the energy release of solid particles in a two phase media at first stages of blast propagation, a series of experiments is described in which an explosive charge is detonated in a box filled with combustible dust in oxygen and other gases. This knowledge is important for the prevention of catastrophic accidents in power stations using pulverized coal, in grain elevators, and in metal grinders. The experiments are simulated numerically and the experimental data are compared to the numerical solution.

ISSN:0010-2202    

DOI:10.1080/00102208108547518

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

—Flame features and combustion process of fuel rich double concentric turbulent jet flames were experimentally examined.

ISSN:0010-2202    

DOI:10.1080/00102208108547519

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

—The departure from frozen flow behavior about a carbon particle in an oxidizing atmosphere, has been discussed in order to obtain the burning rateMover a wide range of the Damköhler numberDg(representing either the particle size or the ambient pressure). The frozen limit (Dg→0) leads to values ofMranging up toM2, the maximum burning rate corresponding to diffusion controlled heterogeneous reactions. By contrast, for finite values ofDgwe find that the burning rate is limited byMlg<M2. The maximum Damköhler numberDg° given by an explicit formula, corresponds to gas phase ignition.

ISSN:0010-2202    

DOI:10.1080/00102208108547520

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The importance of chemical kinetics (heat release rates) in the laminar flame front are discussed. The need and possibilities of studying complex reactions in the flame front for large extents of conversion are considered.

ISSN:0010-2202    

DOI:10.1080/00102208108547521

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor