Publication detail

Characteristics of droplet motion in effervescent sprays

JEDELSKÝ, J. ZAREMBA, M. MALÝ, M. JÍCHA, M.

Original Title

Characteristics of droplet motion in effervescent sprays

Type

conference paper

Language

English

Original Abstract

Time resolved droplet size and velocity measurement was made using Phase-Doppler anemometry in an effervescent spray at GLR of 6 % and operation pressure drops 21 – 52 kPa. The spray shows a size dependent variation of mean as well as fluctuating axial and radial velocities of droplets similarly for all operation regimes. Particles under 13 um follow the gas flow, axially decelerated due to gas expansion. Velocity of medium sized particles is positively size correlated and larger particles keep high velocity, given them during discharge. Fluctuating radial velocity of small particles is larger than that of large particles while fluctuating axial velocity increases with size. Small particles thus reach a ratio of radial to axial velocity fluctuations ~ 0.6 but large particles only ~ 0.1, which indicates large transverse dispersion of small particles. Overall fluctuating velocity ratios smaller than 0.5 document an anisotropic character of the liquid mass fluctuations. Power spectral density (PSD) of axial velocity fluctuations of large droplets is uniform up to 1 kHz, while PSD of smaller particles drops down with frequency for frequencies > 100 Hz. Large particles thus preserve the fluctuations imposed during discharge while the gas turbulence drops with frequency. Turbulence intensity reaches 14 to 21 % depending on pressure. Such high-turbulence character of the flow probably results from a heterogeneous gas–liquid mixture at the discharge.

Keywords

Phase-Doppler analyser, droplet motion, effervescent sprays, Turbulence kinetic energy, Frequency spectra

Authors

JEDELSKÝ, J.; ZAREMBA, M.; MALÝ, M.; JÍCHA, M.

RIV year

2013

Released

25. 3. 2014

Publisher

EDP Sciences

Location

Kutná Hora

ISBN

978-80-260-5375-0

Book

EPJ Web of Conferences

ISBN

2100-014X

Periodical

EPJ Web of Conferences

Year of study

67

Number

1

State

French Republic

Pages from

334

Pages to

339

Pages count

6

URL

https://www.epj-conferences.org/articles/epjconf/abs/2014/04/epjconf_efm-13_02050/epjconf_efm-13_02050.html

Full text in the Digital Library

http://hdl.handle.net/11012/194723

BibTex

@inproceedings{BUT104262,
  author="Jan {Jedelský} and Matouš {Zaremba} and Milan {Malý} and Miroslav {Jícha}",
  title="Characteristics of droplet motion in effervescent sprays",
  booktitle="EPJ Web of Conferences",
  year="2014",
  journal="EPJ Web of Conferences",
  volume="67",
  number="1",
  pages="334--339",
  publisher="EDP Sciences",
  address="Kutná Hora",
  doi="10.1051/epjconf/20146702050",
  isbn="978-80-260-5375-0",
  issn="2100-014X",
  url="https://www.epj-conferences.org/articles/epjconf/abs/2014/04/epjconf_efm-13_02050/epjconf_efm-13_02050.html"
}