Published 12 issues per year
ISSN Print: 1044-5110
ISSN Online: 1936-2684
Indexed in
MEAN BEHAVIOR OF A COAXIAL AIR-BLAST ATOMIZED SPRAY IN A CO-FLOWING AIR STREAM
ABSTRACT
The aim of this article is to characterize the mean behavior of a polydisperse aerosol discharging streamwise into a homogeneous and nearly isotropic grid turbulence. Air-blast coaxial atomization was used to obtain a polydisperse aerosol composed of water droplets with diameters ranging from 5 to 200 μm, with a mean arithmetic size of about 40 μm. Properties of the dispersed phase, such as velocity, size distribution, size-velocity correlation, and number density, were measured by phase Doppler anemometry at several locations behind the grid in the developed jet region, beginning at 100 nozzle diameters downstream of the jet origin, where dilute spray conditions were encountered. The instrument was also used to evaluate the concentration profiles and to compare the mass flux evaluated at six explored stations to the initial flow rate at the nozzle. Further mean velocity profiles of the carrier airflow were obtained by pressure measurements. The mean behavior of the droplets is quantified in terms of mean Stokes numbers, and a turbulent Schmidt number is calculated for the mass and momentum transfer of the two-phase jet entrained by the turbulent co-flow. In the present case, the "dispersion" process appears to be controlled by the dominating inertial effects, and the larger droplets tend to accumulate on the outer edges of the jet.
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Shi W. S., Yamada H., Nishikubo K., Kusaba H., Xu C. N., Novel Structural Behavior of Strontium Aluminate Doped with Europium, Journal of The Electrochemical Society, 151, 5, 2004. Crossref
-
Shi W.S., Yamada H., Nishikubo K., Kusaba H., Xu C.N., Stabilization of beta-SrAl2O4 with Eu Prepared by Spray Pyrolysis, MRS Proceedings, 755, 2002. Crossref
-
Carvalho I.S, Heitor M.V, Santos D, Liquid film disintegration regimes and proposed correlations, International Journal of Multiphase Flow, 28, 5, 2002. Crossref
-
Chen Yung-Cheng, Stårner Sten H., Masri Assaad R., A detailed experimental investigation of well-defined, turbulent evaporating spray jets of acetone, International Journal of Multiphase Flow, 32, 4, 2006. Crossref
-
Lee Sam Goo, Rho Byung Joon, Atomization characteristics in pneumatic counterfiowing internal mixing nozzle, KSME International Journal, 14, 10, 2000. Crossref
-
Fisher Brian T., Weismiller Michael R., Tuttle Steven G., Hinnant Katherine M., Effects of Fluid Properties on Spray Characteristics of a Flow-Blurring Atomizer, Journal of Engineering for Gas Turbines and Power, 140, 4, 2018. Crossref
-
Huilier Daniel G. F., An Overview of the Lagrangian Dispersion Modeling of Heavy Particles in Homogeneous Isotropic Turbulence and Considerations on Related LES Simulations, Fluids, 6, 4, 2021. Crossref