Comparative Analysis of a Single Fuel Droplet Evaporation

Document Type: Research Paper

Authors

Department of Mechanical Engineering, Tarbiat Modares University, Tehran, Iran

Abstract

In this research, the results of comparative analysis of a single fuel droplet evaporation models are presented. Three well-known evaporation models including Spalding, Borman-Johnson and Abramzon-Sirignano models are analyzed using Computational Fluid Dynamic (CFD). The original Spalding model is extended to consider the effects of the Stefan flow, unsteady vaporization, and variable properties. The evaporation models are validated using already existing experimental data. Numerical results show that the Spalding model overestimates the temperature of the droplet surface in comparison with the other two models, although some modifications were made in the aforementioned model. Our final evaluation concludes that Abramzon-Sirignano model predictions are in good agreement with the experimental data. Therefore, in this paper, this model is used for the parametric study of the effects of droplet size, ambient temperature and pressure on the droplet lifetime and temperature. Results indicate that by increasing the droplet size, the lifetime of the droplets will increase and the steady-state droplet temperature is higher at higher ambient pressures and temperature.

Keywords


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