Numerical simulations of near-nozzle exit characteristics for an effervescent atomizer at low gas to liquid mass flow ratio

Deify Law, Thomas Shepard, Paul Strykowski

Research output: Chapter in Book/Report/Conference proceedingConference contribution

3 Scopus citations

Abstract

Effervescent atomization is a process in which a bulk liquid is transformed into a spray of droplets by injecting a small amount of gas into the liquid before it is ejected from the atomizer. Advantages of using effervescent atomization method include larger exit orifices to reduce clogging issues, reduced injection pressures, and lower gas to liquid mass flow ratios (GLR) as compared to pressure or air-blast atomizers [1]. Effervescent atomization has been used in a number of applications including agricultural sprays, paint sprays, combustion for lowering pollutant emissions, spray cooling for gas turbine and medical applications, waste incineration, and process industry applications. In the present work, the near-nozzle exit characteristics of an air-water effervescent atomizer at gas to liquid mass flow ratio such as 0.25% are investigated numerically through two-fluid Eulerian-Eulerian ensemble-averaged modeling. The two-fluid model is solved through the finite volume method. Numerical simulations are performed using the commercial computational fluid dynamics (CFD) code ANSYS FLUENT. The effects of effective (average) air bubble diameter size inside the atomizer, exit nozzle diameter, and injection pressures on the average liquid water jet width are presented. An optimal bubble size is observed for increasing the average liquid jet width which leads to enhanced jet breakup at downstream of the nozzle. The water volume fraction profiles within the sprays are also reported. The numerical results are compared with experimental visualizations and jet-width measurements to further the understanding of the spray characteristics of effervescent atomization for atomizer design.

Original languageEnglish (US)
Title of host publicationSymposia
Subtitle of host publicationFundamental Issues and Perspectives in Fluid Mechanics; Industrial and Environmental Applications of Fluid Mechanics; Issues and Perspectives in Automotive Flows; Gas-Solid Flows: Dedicated to the Memory of Professor Clayton T. Crowe; Numerical Methods for Multiphase Flow; Transport Phenomena in Energy Conversion From Clean and Sustainable Resources; Transport Phenomena in Materials Processing and Manufacturing Processes
PublisherAmerican Society of Mechanical Engineers (ASME)
Volume1C
ISBN (Electronic)9780791846230
DOIs
StatePublished - Jan 1 2014
EventASME 2014 4th Joint US-European Fluids Engineering Division Summer Meeting, FEDSM 2014, Collocated with the ASME 2014 12th International Conference on Nanochannels, Microchannels, and Minichannels - Chicago, United States
Duration: Aug 3 2014Aug 7 2014

Other

OtherASME 2014 4th Joint US-European Fluids Engineering Division Summer Meeting, FEDSM 2014, Collocated with the ASME 2014 12th International Conference on Nanochannels, Microchannels, and Minichannels
CountryUnited States
CityChicago
Period8/3/148/7/14

Fingerprint Dive into the research topics of 'Numerical simulations of near-nozzle exit characteristics for an effervescent atomizer at low gas to liquid mass flow ratio'. Together they form a unique fingerprint.

Cite this