Investigation of the evaporation of single droplets holds a significant importance as it emulates the diluted spray region and helps improve the accuracy of numerical modelling. In the present study, a fan-stirred spherical chamber was employed to generate a homogeneous and isotropic turbulent flow field with negligible mean velocity. This setup was used to investigate the effect of background vapor on the vaporization of a 500 µm pentane droplet in a turbulent flow at elevated pressure and room temperature. Turbulence intensity and pressure were varied, respectively, from stagnant to 1.5 m/s and from 1 to 5 bar. Additionally, the background pentane vapor was altered (on molar basis) from 0 % up to 40 %. The results show that the d2-law is valid throughout all explored test conditions, including in the presence of background vapor. The findings indicated that the presence of background vapor around the evaporating droplet diminishes the droplet vaporization rate under both stagnant and turbulent flow scenarios, with a more pronounced impact at elevated pressure conditions. Furthermore, turbulence is observed to enhance the vaporization rate in the presence of background vapor, with its influence being more substantial at elevated pressure levels and higher concentrations of background vapor. Finally, the experimental data was used to correlate the coupled effect of ambient background vapor, turbulence, and pressure on the vaporization of a pentane droplet in terms of the flow turbulent Reynolds number.
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