Publication detail

Effervescent Atomizer: Influence of the Operation Conditions and Internal Geometry on Spray Structure; Study Using PIV-PLIF

JEDELSKÝ, J. LANDSMANN, M. JÍCHA, M. KUŘITKA, I.

Original Title

Effervescent Atomizer: Influence of the Operation Conditions and Internal Geometry on Spray Structure; Study Using PIV-PLIF

English Title

Effervescent Atomizer: Influence of the Operation Conditions and Internal Geometry on Spray Structure; Study Using PIV-PLIF

Type

conference paper

Language

en

Original Abstract

A single-hole effervescent atomizer spraying light heating oil (LHO) with air as an atomizing medium in the outside-in gas injection configuration is studied. Influence of operation conditions and atomizer design parameters on spray structure is described. Inlet air gauge pressure and gas-to-liquid-ratio by mass (GLR) are varied. Several design parameters are modified: size and number of aeration holes, their location, diameter of the mixing chamber and shape of discharge orifice. 2D velocity field of droplets in the spray and distribution of liquid phase concentration in the plane of the exit orifice axis are evaluated using PIV-PLIF. Results show relatively small influence of the atomizer design on droplet velocity profile and on the concentration distribution. Droplet velocity and concentration data is used for calculation of mass flux and resulting spray cone angle The spray cone half-angle has a value in the range 6.5 to 9.3 deg for all measured configurations and operation conditions. The half-angle increases with: reduction of length/diameter ratio of exit orifice, larger number of aeration holes and aeration holes placed closer to the exit orifice. Influence of the aeration hole size and the influence of mixing chamber diameter is ambiguous. Increase of GLR in the range 2-10 pct leads to increase of the droplet velocity profile mainly near the spray axis and to decrease of spray cone angle, higher atomization pressure causes increase of velocity through all the radial profile and indistinctive expansion or reduction of the cone angle depending on the atomizer design.

English abstract

A single-hole effervescent atomizer spraying light heating oil (LHO) with air as an atomizing medium in the outside-in gas injection configuration is studied. Influence of operation conditions and atomizer design parameters on spray structure is described. Inlet air gauge pressure and gas-to-liquid-ratio by mass (GLR) are varied. Several design parameters are modified: size and number of aeration holes, their location, diameter of the mixing chamber and shape of discharge orifice. 2D velocity field of droplets in the spray and distribution of liquid phase concentration in the plane of the exit orifice axis are evaluated using PIV-PLIF. Results show relatively small influence of the atomizer design on droplet velocity profile and on the concentration distribution. Droplet velocity and concentration data is used for calculation of mass flux and resulting spray cone angle The spray cone half-angle has a value in the range 6.5 to 9.3 deg for all measured configurations and operation conditions. The half-angle increases with: reduction of length/diameter ratio of exit orifice, larger number of aeration holes and aeration holes placed closer to the exit orifice. Influence of the aeration hole size and the influence of mixing chamber diameter is ambiguous. Increase of GLR in the range 2-10 pct leads to increase of the droplet velocity profile mainly near the spray axis and to decrease of spray cone angle, higher atomization pressure causes increase of velocity through all the radial profile and indistinctive expansion or reduction of the cone angle depending on the atomizer design.

Keywords

Effervescent Atomization, Liquid Concentration, Liquid Flux, Spray Structure, Droplet Velocity, PIV-PLIF System

RIV year

2008

Released

08.09.2008

Publisher

Politecnico di Milano

Location

Como Lake, Italy

ISBN

978-88-903712-0-2

Book

22 Annual Conference on Liquid Atomization and Spray Systems

Edition

1

Edition number

1

Pages from

1

Pages to

8

Pages count

8

BibTex


@inproceedings{BUT31183,
  author="Jan {Jedelský} and Michael {Landsmann} and Miroslav {Jícha} and Ivo {Kuřitka}",
  title="Effervescent Atomizer: Influence of the Operation Conditions and Internal Geometry on Spray Structure; Study Using PIV-PLIF",
  annote="A single-hole effervescent atomizer spraying light heating oil (LHO) with air as an atomizing medium in the outside-in gas injection configuration is studied. Influence of operation conditions and atomizer design parameters on spray structure is described. Inlet air gauge pressure and gas-to-liquid-ratio by mass (GLR) are varied. Several design parameters are modified: size and number of aeration holes, their location, diameter of the mixing chamber and shape of discharge orifice. 2D velocity field of droplets in the spray and distribution of liquid phase concentration in the plane of the exit orifice axis are evaluated using PIV-PLIF. Results show relatively small influence of the atomizer design on droplet velocity profile and on the concentration distribution. Droplet velocity and concentration data is used for calculation of mass flux and resulting spray cone angle The spray cone half-angle has a value in the range 6.5 to 9.3 deg for all measured configurations and operation conditions. The half-angle increases with: reduction of length/diameter ratio of exit orifice, larger number of aeration holes and aeration holes placed closer to the exit orifice. Influence of the aeration hole size and the influence of mixing chamber diameter is ambiguous. Increase of GLR in the range 2-10 pct leads to increase of the droplet velocity profile mainly near the spray axis and to decrease of spray cone angle, higher atomization pressure causes increase of velocity through all the radial profile and indistinctive expansion or reduction of the cone angle depending on the atomizer design.",
  address="Politecnico di Milano",
  booktitle="22 Annual Conference on Liquid Atomization and Spray Systems",
  chapter="31183",
  edition="1",
  howpublished="print",
  institution="Politecnico di Milano",
  year="2008",
  month="september",
  pages="1--8",
  publisher="Politecnico di Milano",
  type="conference paper"
}