US EPA

1631901 

Journal Article 

Experimental studies of spray evaporation in turbulent flow 

Sommerfeld, M; Qiu, HH 

1998 

Yes 

International Journal of Heat and Fluid Flow
ISSN: 0142-727X 

19 

1 

10-22 

WOS:000073728300002 

A number of processes in the chemical industry and in combustion science involve the evaporation of atomised liquids in a turbulent environment. To allow an optimisation of such processes and to provide data for the validation of numerical calculations, the spray evaporation in a heated turbulent air stream was studied experimentally. The flow configuration was a pipe expansion with an expansion ratio of 3, where heated air entered through an annulus with the hollow cone spray nozzle being mounted in the centre. In the experiments isopropyl alcohol was used as a liquid because of its high evaporation rate. Measurements were taken for different flow conditions, such as air flow I ate. air temperature, and liquid flow rate in order to provide a set of reliable data. Phase-Doppler anemometry (PDA) was applied to obtain the spatial change of the droplet size spectrum in the flow field and to measure droplet size-velocity correlations. From these local measurements profiles of droplet mean velocities, velocity fluctuations and droplet mean diameters were obtained by averaging over all droplet size classes. Moreover. recent extensions of the PDA signal processing allowed for accurate determination of the droplet mass Bur. from which also the global evaporation rates could also be determined. The data for the different flow conditions also include the inlet conditions for air flow and spray (i.e., for all three velocity components), inlet temperature, and wall temperature profiles. The latter were measured using a thermocouple with a special wall sensor. (C) 1998 Elsevier Science Inc. All rights reserved. 

spray; turbulence; evaporation; phase-Doppler anemometer; droplet velocity; droplet size; droplet mass flux