A Detailed Examination of Gas and Liquid Phase Transient Processes in Convective Droplet Evaporation

Abstract

A finite volume numerical technique has been used to model the evaporation of an n-heptane droplet with an initial Reynolds number of 100 in air at 800 K, 1 atm. The effects of variable thermophysical properties, liquid phase motion and heating, and transient variations in droplet size and velocity are included in the analysis. With appropriate corrections for the effects of variable properties and liquid phase heating, quasi-steady correlations are shown to predict accurately the transient histories of the drag coefficient and Nusselt and Sherwood numbers. For the case investigated here, the transient effects of importance were the variation in droplet velocity, the decline in the liquid phase velocities, and the rise in the droplet surface and volume average temperatures. In spite of the transient rise in the droplet temperature, the nature of the liquid phase heating, as characterised by the liquid Nusselt number, was found to remain constant during most of the droplet lifetime.

Modeling Temperature Distribution Inside an Emulsion Fuel Droplet Under Convective Heating: A Key to Predicting Microexplosion and Puffing

“…4c. It can be seen that the obtained simulation results are in good agreement with the reported ones (Haywood et al, 1989;Chaing et al, 1992).…”

Advanced models of fuel droplet heating and evaporation

“…Also, in this paper a detailed analysis of the experimental data on droplets suspended at the end of a tube in a wind tunnel was presented. This analysis eventually led to the following correlation [64,66,158]:…”

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A model for a non-uniform spray evaporator taking into account the effect of non-isothermal polydisperse droplets

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