CFD-Based Multiscale Modelling of Bubble-Particle Collision Rates and Efficiencies in a Flotation Ce...
Download
1 / 19

CFD-Based Multiscale Modelling of Bubble-Particle Collision Rates and Efficiencies in a Flotation Cell - PowerPoint PPT Presentation


  • 196 Views
  • Uploaded on

CFD-Based Multiscale Modelling of Bubble-Particle Collision Rates and Efficiencies in a Flotation Cell. Tom Liu, Peter Koh and Phil Schwarz CSIRO Minerals. Multiscale Modelling in Industrial Systems . Team Members: Phil Schwarz, CM (Project leader) Nick Stokes, CMIS Murray Rudman, CMIT

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'CFD-Based Multiscale Modelling of Bubble-Particle Collision Rates and Efficiencies in a Flotation Cell' - butterfly


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Slide1 l.jpg

CFD-Based Multiscale Modelling of Bubble-Particle Collision Rates and Efficiencies in a Flotation Cell

Tom Liu, Peter Koh and Phil Schwarz

CSIRO Minerals


Multiscale modelling in industrial systems l.jpg
Multiscale Modelling in Industrial Systems Rates and Efficiencies in a Flotation Cell

Team Members:

Phil Schwarz, CM (Project leader)

Nick Stokes, CMIS

Murray Rudman, CMIT

Alf Uhlherr, CMS

Peter Witt, CM

Paul Cleary, CMIS

Tom Liu, CM


Outline l.jpg
Outline Rates and Efficiencies in a Flotation Cell

  • Background information

  • Brief introduction to multiscale modelling

  • Brief introduction to the modelling of flotation processes

  • CFD-based multiscale modelling strategy for a flotation cell

  • Some simulation results and future works

  • Conclusions


Background information l.jpg
Background Information Rates and Efficiencies in a Flotation Cell

Froth flotation is a complex three phase physico-chemical processes

Prediction of flotation kinetics has not been possible


Life is not simple l.jpg
Life Is Not Simple Rates and Efficiencies in a Flotation Cell

The extension of direct free-surface modelling techniques to resolve every bubble and particle in a industrial-scale vessel would require far more computational power than will be available


Multiscale modelling l.jpg

Jenkins Rates and Efficiencies in a Flotation Cellet al.ICCS 2005, Atlanta

Multiscale Modelling


Multiscale modelling methods l.jpg

Jenkins Rates and Efficiencies in a Flotation Cellet al., ICCS 2005, Atlanta

Continuum model

Molecular model

Multiscale Modelling Methods

  • Domain decomposition method

  • Process decomposition method

Jenkins et al.ICCS 2005, Atlanta


Current modelling methods for flotation processes l.jpg

Koh Rates and Efficiencies in a Flotation Cellet al.(2003)

Current Modelling Methods For Flotation Processes

  • Correlation methods

  • First-principles methods

  • CFD methods


Examples of problems l.jpg
Examples of Problems Rates and Efficiencies in a Flotation Cell

?

Nguyen & Kmet (1992)


Examples of problems10 l.jpg
Examples of Problems Rates and Efficiencies in a Flotation Cell

Koh & Schwarz (2003)


Examples of problems11 l.jpg

Prediction formula: Rates and Efficiencies in a Flotation Cell

Quiescent condition

Bubble size

Bubble rising velocity

Bubble Re

Collision efficiency

Flotation cell:

Turbulent condition

Stirring speed, cell structure, gas flow rate, … Bubble size, bubble velocity, bubble Re

Collision efficiency

Examples of Problems


Structure of cfd based multiscale flotation modelling l.jpg

Five different types of computational experiments are defined to calculate:

(1)Bubble-particle collision frequencies

(2)Bubble-particle collision efficiencies

(3)Bubble-particle attachment and detachment rates

(4)Drag coefficients for bubbles

(5)Bubble coalescence and break-up rates

CFD Model with time averaged RANS and multifluid techniques through suitable microscale closure relations

Structure Of CFD-based Multiscale Flotation Modelling


Some results l.jpg
Some Results defined to calculate:

  • A wavelet-based adaptive mesh scheme to track moving free surfaces

  • 2D CFD turbulent collision model

  • 3D CFD model for Non-Newtonian drag coefficients


Bubble rising simulation l.jpg
Bubble Rising Simulation defined to calculate:

A wavelet-based adaptive mesh scheme was embedded into CFX to track moving free surfaces


Bubble particle collisions l.jpg
Bubble-Particle Collisions defined to calculate:


Slide16 l.jpg
Comparisons Between CFD Predicted Turbulent Collision Efficiencies and Laminar Collision Efficiencies



Further works l.jpg
Further works Non-Newtonian Fluids

  • 3D CFD turbulent collision model

  • LES of bubble-particle collision

  • 2D CFD turbulent collision frequency model

  • CFD bubble coalescence/breakup model

  • Coupling macroscale model to microscale models


Conclusions l.jpg
Conclusions Non-Newtonian Fluids

  • Multiscale modelling strategy for a flotation cell

  • Wavelet-based adaptive moving mesh scheme

  • CFD-based numerical experiments for turbulent bubble-particle collisions and Non-Newtonian drag coefficients

  • Further works


ad