A New Mathematical Model for Cloud Flame Structure with Premixed Organic Particles

Document Type : Research Article

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Abstract

A new mathematical model is introduced to predict structure of premixed flame propagating in combustible systems, with uniformly distributed volatile fuel particles and air. In the present paper the flame structure is divided into four zones that consists of a preheat zone, an extensive particles vaporization zone, an asymptotically thin reaction zone, and finally a post flame zone. It is presumed that the fuel particles vaporize first to yield a gaseous fuel, which is subsequently oxidized. The study involves the Damkohler number , the ratio of chemical reaction rate to vaporization rate, and the Zeldovich number , the nondimensional form of activation energy, as essential parameters. Finally, with considering unity Lewis number and neglecting the latent heat of vaporization, for several equivalence ratios and several diameters of particles the analysis yields results for the mass fraction of the fine-solid particles, mass fraction of the fuel in the gaseous phase and nondimensional temperature. This prediction is in agreement with experimental observations of fine particles combustion.

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References

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