Experimental validation of analytical models for liquid film breakup on rotating substrates

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Many models for predicting the breakup of liquid films spreading over solid substrates have been proposed over the years, each taking a different approach to modelling the minimum stable film height. There is not a lot of reliable experimental data in the literature for validating these models, however, as previous measurement campaigns have generally relied on the relatively weak gravitational force as a wetting driver, making the results sensitive to minor flow disturbances and flaws in the substrate. The present work considers experimentally the breakup of films spreading radially over rapidly rotating substrates, where the much stronger centrifugal force takes the place of gravity. An empirical correlation has been derived from the presently generated data and compared with analytical predictions. The predictions of the analytical wetting models, appropriately modified, were additionally validated against the observed radial breakup locations. The models which considered an equilibrium of surface tension and inertia were found to give the best overall agreement with the data. However, it was also shown that the retarding effect of viscous shear needs to be taken into account in the modelling and that a blended approach incorporating both inertial and viscous length scales is necessary in order to obtain a generally valid model.

LanguageEnglish
Pages118-129
Number of pages12
JournalChemical Engineering Science
Volume202
DOIs
StatusPublished - 20 Jul 2019

Fingerprint

Drop breakup
Experimental Validation
Breakup
Liquid films
Analytical Model
Analytical models
Rotating
Substrate
Liquid
Substrates
Wetting
Centrifugal Force
Model
Prediction
Modeling
Surface Tension
Length Scale
Inertia
Driver
Surface tension

Keywords

  • Film breakup
  • Model validation
  • Rotating flow
  • Wetting

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Chemistry(all)
  • Industrial and Manufacturing Engineering

Fields of Expertise

  • Mobility & Production

Cite this

Experimental validation of analytical models for liquid film breakup on rotating substrates. / Line, Hakon; Steiner, Helfried; Brenn, Günter.

In: Chemical Engineering Science, Vol. 202, 20.07.2019, p. 118-129.

Research output: Contribution to journalArticleResearchpeer-review

@article{2fc9ecccdb4a41709226691d8fd0b799,
title = "Experimental validation of analytical models for liquid film breakup on rotating substrates",
abstract = "Many models for predicting the breakup of liquid films spreading over solid substrates have been proposed over the years, each taking a different approach to modelling the minimum stable film height. There is not a lot of reliable experimental data in the literature for validating these models, however, as previous measurement campaigns have generally relied on the relatively weak gravitational force as a wetting driver, making the results sensitive to minor flow disturbances and flaws in the substrate. The present work considers experimentally the breakup of films spreading radially over rapidly rotating substrates, where the much stronger centrifugal force takes the place of gravity. An empirical correlation has been derived from the presently generated data and compared with analytical predictions. The predictions of the analytical wetting models, appropriately modified, were additionally validated against the observed radial breakup locations. The models which considered an equilibrium of surface tension and inertia were found to give the best overall agreement with the data. However, it was also shown that the retarding effect of viscous shear needs to be taken into account in the modelling and that a blended approach incorporating both inertial and viscous length scales is necessary in order to obtain a generally valid model.",
keywords = "Film breakup, Model validation, Rotating flow, Wetting",
author = "Hakon Line and Helfried Steiner and G{\"u}nter Brenn",
year = "2019",
month = "7",
day = "20",
doi = "10.1016/j.ces.2019.03.014",
language = "English",
volume = "202",
pages = "118--129",
journal = "Chemical Engineering Science",
issn = "0009-2509",
publisher = "Elsevier B.V.",

}

TY - JOUR

T1 - Experimental validation of analytical models for liquid film breakup on rotating substrates

AU - Line, Hakon

AU - Steiner, Helfried

AU - Brenn, Günter

PY - 2019/7/20

Y1 - 2019/7/20

N2 - Many models for predicting the breakup of liquid films spreading over solid substrates have been proposed over the years, each taking a different approach to modelling the minimum stable film height. There is not a lot of reliable experimental data in the literature for validating these models, however, as previous measurement campaigns have generally relied on the relatively weak gravitational force as a wetting driver, making the results sensitive to minor flow disturbances and flaws in the substrate. The present work considers experimentally the breakup of films spreading radially over rapidly rotating substrates, where the much stronger centrifugal force takes the place of gravity. An empirical correlation has been derived from the presently generated data and compared with analytical predictions. The predictions of the analytical wetting models, appropriately modified, were additionally validated against the observed radial breakup locations. The models which considered an equilibrium of surface tension and inertia were found to give the best overall agreement with the data. However, it was also shown that the retarding effect of viscous shear needs to be taken into account in the modelling and that a blended approach incorporating both inertial and viscous length scales is necessary in order to obtain a generally valid model.

AB - Many models for predicting the breakup of liquid films spreading over solid substrates have been proposed over the years, each taking a different approach to modelling the minimum stable film height. There is not a lot of reliable experimental data in the literature for validating these models, however, as previous measurement campaigns have generally relied on the relatively weak gravitational force as a wetting driver, making the results sensitive to minor flow disturbances and flaws in the substrate. The present work considers experimentally the breakup of films spreading radially over rapidly rotating substrates, where the much stronger centrifugal force takes the place of gravity. An empirical correlation has been derived from the presently generated data and compared with analytical predictions. The predictions of the analytical wetting models, appropriately modified, were additionally validated against the observed radial breakup locations. The models which considered an equilibrium of surface tension and inertia were found to give the best overall agreement with the data. However, it was also shown that the retarding effect of viscous shear needs to be taken into account in the modelling and that a blended approach incorporating both inertial and viscous length scales is necessary in order to obtain a generally valid model.

KW - Film breakup

KW - Model validation

KW - Rotating flow

KW - Wetting

UR - http://www.scopus.com/inward/record.url?scp=85063220481&partnerID=8YFLogxK

U2 - 10.1016/j.ces.2019.03.014

DO - 10.1016/j.ces.2019.03.014

M3 - Article

VL - 202

SP - 118

EP - 129

JO - Chemical Engineering Science

T2 - Chemical Engineering Science

JF - Chemical Engineering Science

SN - 0009-2509

ER -