Imperial College London
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ProfessorAlexTaylor

Faculty of Engineering, Department of Mechanical Engineering

Professor
 
 
 
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Contact

 

+44 (0)20 7594 7042a.m.taylor

 
 
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Location

 

618City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Sahu:2018:10.1017/jfm.2018.247,
author = {Sahu, S and Hardalupas, I and Taylor, AMKP},
doi = {10.1017/jfm.2018.247},
journal = {Journal of Fluid Mechanics},
pages = {37--81},
title = {Interaction of droplet dispersion and evaporation in a polydispersed spray},
url = {http://dx.doi.org/10.1017/jfm.2018.247},
volume = {846},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The interaction between droplet dispersion and evaporation in an acetone spray evaporating under ambient conditions is experimentally studied with an aim to understand the physics behind the spatial correlation between the local vapour mass fraction and droplets. The influence of gas-phase turbulence and droplet–gas slip velocity of such correlations is examined, while the focus is on the consequence of droplet clustering on collective evaporation of droplet clouds. Simultaneous and planar measurements of droplet size, velocity and number density, and vapour mass fraction around the droplets, were obtained by combining the interferometric laser imaging for droplet sizing and planar laser induced fluorescence techniques (Sahu et al., Exp. Fluids, vol. 55, 1673, 2014b, pp. 1–21). Comparison with droplet measurements in a non-evaporating water spray under the same flow conditions showed that droplet evaporation leads to higher fluctuations of droplet number density and velocity relative to the respective mean values. While the mean droplet–gas slip velocity was found to be negligibly small, the vaporization Damköhler number ( ) was approximately ‘one’, which means the droplet evaporation time and the characteristic time scale of large eddies are of the same order. Thus, the influence of the convective effect on droplet evaporation is not expected to be significant in comparison to the instantaneous fluctuations of slip velocity, which refers to the direct effect of turbulence. An overall linearly increasing trend was observed in the scatter plot of the instantaneous values of droplet number density ( ) and vapour mass fraction ( ). Accordingly, the correlation coefficient of fluctuations of vapour mass fraction and droplet number density ( ) was relatively high ( ) implying moderately high correlation. However, considerable spread of the versus scatter plot along both coordinates demonstrated the influence on droplet evaporation due t
AU  - Sahu,S
AU  - Hardalupas,I
AU  - Taylor,AMKP
DO  - 10.1017/jfm.2018.247
EP  - 81
PY  - 2018///
SN  - 0022-1120
SP  - 37
TI  - Interaction of droplet dispersion and evaporation in a polydispersed spray
T2  - Journal of Fluid Mechanics
UR  - http://dx.doi.org/10.1017/jfm.2018.247
UR  - https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/interaction-of-droplet-dispersion-and-evaporation-in-a-polydispersed-spray/50BC8CB7B5A0D24B900FE983639533E1
UR  - http://hdl.handle.net/10044/1/57946
VL  - 846
ER  -
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